mesfun10.miz
begin
reserve X for non
empty
set,
F for
with_the_same_dom
Functional_Sequence of X,
ExtREAL ,
seq,seq1,seq2 for
ExtREAL_sequence,
x for
Element of X,
a,r for
R_eal,
n,m,k for
Nat;
theorem ::
MESFUN10:1
Th1: (for n be
Nat holds (seq1
. n)
<= (seq2
. n)) implies (
inf (
rng seq1))
<= (
inf (
rng seq2))
proof
assume
A1: for n be
Nat holds (seq1
. n)
<= (seq2
. n);
now
let x be
ExtReal;
A2:
now
let n be
Element of
NAT ;
(
dom seq1)
=
NAT by
FUNCT_2:def 1;
then
A3: (seq1
. n)
in (
rng seq1) by
FUNCT_1:def 3;
A4: (seq1
. n)
<= (seq2
. n) by
A1;
(
inf (
rng seq1)) is
LowerBound of (
rng seq1) by
XXREAL_2:def 4;
then (
inf (
rng seq1))
<= (seq1
. n) by
A3,
XXREAL_2:def 2;
hence (
inf (
rng seq1))
<= (seq2
. n) by
A4,
XXREAL_0: 2;
end;
assume x
in (
rng seq2);
then ex z be
object st z
in (
dom seq2) & x
= (seq2
. z) by
FUNCT_1:def 3;
hence (
inf (
rng seq1))
<= x by
A2;
end;
then (
inf (
rng seq1)) is
LowerBound of (
rng seq2) by
XXREAL_2:def 2;
hence thesis by
XXREAL_2:def 4;
end;
theorem ::
MESFUN10:2
Th2: (for n be
Nat holds (seq1
. n)
<= (seq2
. n)) implies ((
inferior_realsequence seq1)
. k)
<= ((
inferior_realsequence seq2)
. k) & ((
superior_realsequence seq1)
. k)
<= ((
superior_realsequence seq2)
. k)
proof
reconsider k1 = k as
Element of
NAT by
ORDINAL1:def 12;
assume
A1: for n be
Nat holds (seq1
. n)
<= (seq2
. n);
A2:
now
let n be
Nat;
A3: ((seq2
^\ k1)
. n)
= (seq2
. (n
+ k)) by
NAT_1:def 3;
((seq1
^\ k1)
. n)
= (seq1
. (n
+ k)) by
NAT_1:def 3;
hence ((seq1
^\ k1)
. n)
<= ((seq2
^\ k1)
. n) by
A1,
A3;
end;
then (
sup (seq1
^\ k1))
<= (
sup (seq2
^\ k1)) by
MESFUNC5: 55;
then
A4: ((
superior_realsequence seq1)
. k)
<= (
sup (seq2
^\ k1)) by
RINFSUP2: 27;
(
inf (seq1
^\ k1))
<= (
inf (seq2
^\ k1)) by
A2,
Th1;
then ((
inferior_realsequence seq1)
. k)
<= (
inf (seq2
^\ k1)) by
RINFSUP2: 27;
hence thesis by
A4,
RINFSUP2: 27;
end;
theorem ::
MESFUN10:3
Th3: (for n be
Nat holds (seq1
. n)
<= (seq2
. n)) implies (
lim_inf seq1)
<= (
lim_inf seq2) & (
lim_sup seq1)
<= (
lim_sup seq2)
proof
assume for n be
Nat holds (seq1
. n)
<= (seq2
. n);
then for n be
Nat holds ((
inferior_realsequence seq1)
. n)
<= ((
inferior_realsequence seq2)
. n) & ((
superior_realsequence seq1)
. n)
<= ((
superior_realsequence seq2)
. n) by
Th2;
hence thesis by
Th1,
MESFUNC5: 55;
end;
theorem ::
MESFUN10:4
Th4: (for n be
Nat holds (seq
. n)
>= a) implies (
inf seq)
>= a
proof
assume
A1: for n be
Nat holds (seq
. n)
>= a;
now
let x be
ExtReal;
assume x
in (
rng seq);
then ex z be
object st z
in (
dom seq) & x
= (seq
. z) by
FUNCT_1:def 3;
hence x
>= a by
A1;
end;
then a is
LowerBound of (
rng seq) by
XXREAL_2:def 2;
hence thesis by
XXREAL_2:def 4;
end;
theorem ::
MESFUN10:5
Th5: (for n be
Nat holds (seq
. n)
<= a) implies (
sup seq)
<= a
proof
assume
A1: for n be
Nat holds (seq
. n)
<= a;
now
let x be
ExtReal;
assume x
in (
rng seq);
then ex z be
object st z
in (
dom seq) & x
= (seq
. z) by
FUNCT_1:def 3;
hence x
<= a by
A1;
end;
then a is
UpperBound of (
rng seq) by
XXREAL_2:def 1;
hence thesis by
XXREAL_2:def 3;
end;
theorem ::
MESFUN10:6
Th6: for n be
Element of
NAT st x
in (
dom (
inf (F
^\ n))) holds ((
inf (F
^\ n))
. x)
= (
inf ((F
# x)
^\ n))
proof
let n be
Element of
NAT ;
now
reconsider g = F as
sequence of (
PFuncs (X,
ExtREAL ));
let k be
Element of
NAT ;
(((F
^\ n)
# x)
. k)
= (((F
^\ n)
. k)
. x) by
MESFUNC5:def 13;
then (((F
^\ n)
# x)
. k)
= ((g
. (n
+ k))
. x) by
NAT_1:def 3;
then (((F
^\ n)
# x)
. k)
= ((F
# x)
. (n
+ k)) by
MESFUNC5:def 13;
hence (((F
^\ n)
# x)
. k)
= (((F
# x)
^\ n)
. k) by
NAT_1:def 3;
end;
then
A1: ((F
^\ n)
# x)
= ((F
# x)
^\ n) by
FUNCT_2: 63;
assume x
in (
dom (
inf (F
^\ n)));
hence thesis by
A1,
MESFUNC8:def 3;
end;
reserve S for
SigmaField of X,
M for
sigma_Measure of S,
E for
Element of S;
::$Notion-Name
theorem ::
MESFUN10:7
Th7: E
= (
dom (F
.
0 )) & (for n holds (F
. n) is
nonnegative & (F
. n) is E
-measurable) implies ex I be
ExtREAL_sequence st (for n holds (I
. n)
= (
Integral (M,(F
. n)))) & (
Integral (M,(
lim_inf F)))
<= (
lim_inf I)
proof
assume that
A1: E
= (
dom (F
.
0 )) and
A2: for n holds (F
. n) is
nonnegative & (F
. n) is E
-measurable;
set H = (
inferior_realsequence F);
deffunc
G(
Element of
NAT ) = (
inf (F
^\ $1));
consider G be
Function such that
A3: (
dom G)
=
NAT & for n be
Element of
NAT holds (G
. n)
=
G(n) from
FUNCT_1:sch 4;
now
let n be
Nat;
n
in
NAT by
ORDINAL1:def 12;
then (G
. n)
= (
inf (F
^\ n)) by
A3;
hence (G
. n) is
PartFunc of X,
ExtREAL ;
end;
then
reconsider G as
Functional_Sequence of X,
ExtREAL by
A3,
SEQFUNC: 1;
A4: for n be
Element of
NAT holds (G
. n)
= ((
inferior_realsequence F)
. n)
proof
let n be
Element of
NAT ;
((
inferior_realsequence F)
. n)
= (
inf (F
^\ n)) by
MESFUNC8: 8;
hence thesis by
A3;
end;
then
A5: G
= (
inferior_realsequence F) by
FUNCT_2: 63;
reconsider G as
with_the_same_dom
Functional_Sequence of X,
ExtREAL by
A4,
FUNCT_2: 63;
A6: (
dom (H
.
0 ))
= (
dom (G
.
0 )) by
A4;
A7: for n,m be
Nat, x be
Element of X st n
<= m & x
in E holds ((G
. n)
. x)
<= ((G
. m)
. x) & ((G
# x)
. n)
<= ((G
# x)
. m)
proof
let n,m be
Nat, x be
Element of X;
reconsider n1 = n, m1 = m as
Element of
NAT by
ORDINAL1:def 12;
assume that
A8: n
<= m and
A9: x
in E;
(H
# x)
= (
inferior_realsequence (F
# x)) by
A1,
A9,
MESFUNC8: 7;
then ((H
# x)
. n1)
<= ((H
# x)
. m1) by
A8,
RINFSUP2: 7;
then ((H
. n)
. x)
<= ((H
# x)
. m) by
MESFUNC5:def 13;
hence ((G
. n)
. x)
<= ((G
. m)
. x) by
A5,
MESFUNC5:def 13;
then ((G
# x)
. n)
<= ((G
. m)
. x) by
MESFUNC5:def 13;
hence thesis by
MESFUNC5:def 13;
end;
A10:
now
let x be
Element of X;
assume x
in E;
then for n,m be
Nat st m
<= n holds ((G
# x)
. m)
<= ((G
# x)
. n) by
A7;
then (G
# x) is
non-decreasing by
RINFSUP2: 7;
hence (G
# x) is
convergent by
RINFSUP2: 37;
end;
deffunc
I(
Element of
NAT ) = (
Integral (M,(F
. $1)));
consider I be
sequence of
ExtREAL such that
A11: for n be
Element of
NAT holds (I
. n)
=
I(n) from
FUNCT_2:sch 4;
A12: for n be
Nat holds (G
. n) is E
-measurable by
A1,
A2,
A5,
MESFUNC8: 20;
A13: (
dom (H
.
0 ))
= (
dom (F
.
0 )) by
MESFUNC8:def 5;
then
A14: (
dom (
lim G))
= E by
A1,
A6,
MESFUNC8:def 9;
for x be
object st x
in (
dom (G
.
0 )) holds
0
<= ((G
.
0 )
. x)
proof
let x be
object;
assume
A15: x
in (
dom (G
.
0 ));
then
reconsider x as
Element of X;
A16:
now
let n be
Nat;
(F
. n) is
nonnegative by
A2;
then
0
<= ((F
. n)
. x) by
SUPINF_2: 51;
then
0
<= ((F
# x)
. (
0
+ n)) by
MESFUNC5:def 13;
hence
0.
<= (((F
# x)
^\
0 )
. n) by
NAT_1:def 3;
end;
((F
^\
0 )
.
0 )
= (F
. (
0
+
0 )) by
NAT_1:def 3;
then (
dom (
inf (F
^\
0 )))
= (
dom (F
.
0 )) by
MESFUNC8:def 3;
then ((
inf (F
^\
0 ))
. x)
= (
inf ((F
# x)
^\
0 )) by
A13,
A6,
A15,
Th6;
then ((G
.
0 )
. x)
= (
inf ((F
# x)
^\
0 )) by
A3;
hence thesis by
A16,
Th4;
end;
then
A17: (G
.
0 ) is
nonnegative by
SUPINF_2: 52;
for n,m be
Nat st n
<= m holds for x be
Element of X st x
in E holds ((G
. n)
. x)
<= ((G
. m)
. x) by
A7;
then
consider J be
ExtREAL_sequence such that
A18: for n be
Nat holds (J
. n)
= (
Integral (M,(G
. n))) and
A19: J is
convergent and
A20: (
Integral (M,(
lim G)))
= (
lim J) by
A1,
A13,
A6,
A17,
A12,
A10,
MESFUNC9: 52;
reconsider I as
ExtREAL_sequence;
for n be
Nat holds (J
. n)
<= (I
. n)
proof
let n be
Nat;
A21: (
dom (F
. n))
= E by
A1,
MESFUNC8:def 2;
A22: (F
. n) is
nonnegative by
A2;
A23: n is
Element of
NAT by
ORDINAL1:def 12;
A24:
now
let x be
Element of X;
assume
A25: x
in (
dom (G
. n));
((
inferior_realsequence (F
# x))
. n)
<= ((F
# x)
. n) by
RINFSUP2: 8;
then ((H
. n)
. x)
<= ((F
# x)
. n) by
A5,
A25,
MESFUNC8:def 5;
then ((H
. n)
. x)
<= ((F
. n)
. x) by
MESFUNC5:def 13;
hence ((G
. n)
. x)
<= ((F
. n)
. x) by
A4,
A23;
end;
A26: (F
. n) is E
-measurable by
A2;
A27: (G
. n) is E
-measurable by
A1,
A2,
A5,
MESFUNC8: 20;
A28: (
dom (G
. n))
= E by
A1,
A13,
A6,
MESFUNC8:def 2;
A29:
now
let x be
object;
assume
A30: x
in (
dom (G
. n));
0
<= ((G
.
0 )
. x) by
A17,
SUPINF_2: 51;
hence
0
<= ((G
. n)
. x) by
A7,
A28,
A30;
end;
then (G
. n) is
nonnegative by
SUPINF_2: 52;
then (
integral+ (M,(G
. n)))
<= (
integral+ (M,(F
. n))) by
A21,
A28,
A26,
A27,
A22,
A24,
MESFUNC5: 85;
then (
Integral (M,(G
. n)))
<= (
integral+ (M,(F
. n))) by
A28,
A27,
A29,
MESFUNC5: 88,
SUPINF_2: 52;
then
A31: (
Integral (M,(G
. n)))
<= (
Integral (M,(F
. n))) by
A21,
A26,
A22,
MESFUNC5: 88;
(I
. n)
= (
Integral (M,(F
. n))) by
A11,
A23;
hence thesis by
A18,
A31;
end;
then (
lim_inf J)
<= (
lim_inf I) by
Th3;
then
A32: (
lim J)
<= (
lim_inf I) by
A19,
RINFSUP2: 41;
A33: (
dom (
sup G))
= E by
A1,
A13,
A6,
MESFUNC8:def 4;
now
let x be
Element of X;
assume
A34: x
in (
dom (
lim G));
then for n,m be
Nat st m
<= n holds ((G
# x)
. m)
<= ((G
# x)
. n) by
A7,
A14;
then (G
# x) is
non-decreasing by
RINFSUP2: 7;
then
A35: (
lim (G
# x))
= (
sup (G
# x)) by
RINFSUP2: 37;
((
sup G)
. x)
= (
sup (G
# x)) by
A14,
A33,
A34,
MESFUNC8:def 4;
hence ((
lim G)
. x)
= ((
sup G)
. x) by
A34,
A35,
MESFUNC8:def 9;
end;
then
A36: (
lim G)
= (
sup G) by
A14,
A33,
PARTFUN1: 5;
take I;
for n be
Nat holds (I
. n)
= (
Integral (M,(F
. n)))
proof
let n be
Nat;
n is
Element of
NAT by
ORDINAL1:def 12;
hence thesis by
A11;
end;
hence thesis by
A5,
A20,
A36,
A32,
MESFUNC8: 11;
end;
begin
theorem ::
MESFUN10:8
Th8: for Y be non
empty
Subset of
ExtREAL , r be
R_eal st r
in
REAL holds (
sup (
{r}
+ Y))
= ((
sup
{r})
+ (
sup Y))
proof
let Y be non
empty
Subset of
ExtREAL ;
let r be
R_eal;
set X =
{r};
assume
A1: r
in
REAL ;
set W = (X
+ Y);
A2: (
- r)
<>
-infty by
A1,
XXREAL_3: 23;
A3: (
- r)
<>
+infty by
A1,
XXREAL_3: 23;
now
let z be
object;
assume z
in ((
- X)
+ W);
then
consider x,y be
R_eal such that
A4: z
= (x
+ y) and
A5: x
in (
- X) and
A6: y
in W;
consider x1,y1 be
R_eal such that
A7: y
= (x1
+ y1) and
A8: x1
in X and
A9: y1
in Y by
A6;
(
- x)
in (
- (
- X)) by
A5;
then (
- x)
in X;
then (
- x)
= r by
TARSKI:def 1;
then z
= ((
- r)
+ (r
+ y1)) by
A4,
A8,
A7,
TARSKI:def 1;
then z
= (((
- r)
+ r)
+ y1) by
A1,
A3,
A2,
XXREAL_3: 29;
then z
= (
0.
+ y1) by
XXREAL_3: 7;
hence z
in Y by
A9,
XXREAL_3: 4;
end;
then
A10: ((
- X)
+ W)
c= Y by
TARSKI:def 3;
A11: r
in X by
TARSKI:def 1;
now
let z be
object;
assume
A12: z
in Y;
then
reconsider y = z as
Element of
ExtREAL ;
((r
+ y)
- r)
= (((
- r)
+ r)
+ y) by
A1,
A3,
A2,
XXREAL_3: 29;
then ((r
+ y)
- r)
= (
0.
+ y) by
XXREAL_3: 7;
then
A13: y
= ((r
+ y)
- r) by
XXREAL_3: 4;
A14: (
- r)
in (
- X) by
A11;
(r
+ y)
in W by
A11,
A12;
hence z
in ((
- X)
+ W) by
A14,
A13;
end;
then Y
c= ((
- X)
+ W) by
TARSKI:def 3;
then Y
= ((
- X)
+ W) by
A10,
XBOOLE_0:def 10;
then (
sup Y)
<= ((
sup W)
+ (
sup (
- X))) by
SUPINF_2: 8;
then (
sup Y)
<= ((
sup (X
+ Y))
+ (
- (
inf X))) by
SUPINF_2: 15;
then (
sup Y)
<= ((
sup (X
+ Y))
- r) by
XXREAL_2: 13;
then (r
+ (
sup Y))
<= (
sup (X
+ Y)) by
A1,
XXREAL_3: 57;
then
A15: ((
sup X)
+ (
sup Y))
<= (
sup (X
+ Y)) by
XXREAL_2: 11;
(
sup (X
+ Y))
<= ((
sup X)
+ (
sup Y)) by
SUPINF_2: 8;
hence thesis by
A15,
XXREAL_0: 1;
end;
theorem ::
MESFUN10:9
Th9: for Y be non
empty
Subset of
ExtREAL , r be
R_eal st r
in
REAL holds (
inf (
{r}
+ Y))
= ((
inf
{r})
+ (
inf Y))
proof
let Y be non
empty
Subset of
ExtREAL ;
let r be
R_eal;
set X =
{r};
assume
A1: r
in
REAL ;
set W = (X
+ Y);
set Z = (
- X);
A2: (
- r)
<>
-infty by
A1,
XXREAL_3: 23;
A3: (
- r)
<>
+infty by
A1,
XXREAL_3: 23;
now
let z be
object;
assume z
in (Z
+ W);
then
consider x,y be
R_eal such that
A4: z
= (x
+ y) and
A5: x
in Z and
A6: y
in W;
consider x1,y1 be
R_eal such that
A7: y
= (x1
+ y1) and
A8: x1
in X and
A9: y1
in Y by
A6;
(
- x)
in (
- Z) by
A5;
then (
- x)
in X;
then (
- x)
= r by
TARSKI:def 1;
then z
= ((
- r)
+ (r
+ y1)) by
A4,
A8,
A7,
TARSKI:def 1;
then z
= (((
- r)
+ r)
+ y1) by
A1,
A3,
A2,
XXREAL_3: 29;
then z
= (
0.
+ y1) by
XXREAL_3: 7;
hence z
in Y by
A9,
XXREAL_3: 4;
end;
then
A10: (Z
+ W)
c= Y by
TARSKI:def 3;
A11: r
in X by
TARSKI:def 1;
now
let z be
object;
assume
A12: z
in Y;
then
reconsider y = z as
Element of
ExtREAL ;
((r
+ y)
- r)
= (((
- r)
+ r)
+ y) by
A1,
A3,
A2,
XXREAL_3: 29;
then ((r
+ y)
- r)
= (
0.
+ y) by
XXREAL_3: 7;
then
A13: y
= ((r
+ y)
- r) by
XXREAL_3: 4;
A14: (
- r)
in Z by
A11;
(r
+ y)
in W by
A11,
A12;
hence z
in (Z
+ W) by
A14,
A13;
end;
then Y
c= (Z
+ W) by
TARSKI:def 3;
then Y
= (Z
+ W) by
A10,
XBOOLE_0:def 10;
then (
inf Y)
>= ((
inf W)
+ (
inf Z)) by
SUPINF_2: 9;
then (
inf Y)
>= ((
inf (X
+ Y))
+ (
- (
sup X))) by
SUPINF_2: 14;
then (
inf Y)
>= ((
inf (X
+ Y))
- r) by
XXREAL_2: 11;
then (r
+ (
inf Y))
>= (
inf (X
+ Y)) by
A1,
XXREAL_3: 52;
then
A15: ((
inf X)
+ (
inf Y))
>= (
inf (X
+ Y)) by
XXREAL_2: 13;
(
inf (X
+ Y))
>= ((
inf X)
+ (
inf Y)) by
SUPINF_2: 9;
hence thesis by
A15,
XXREAL_0: 1;
end;
theorem ::
MESFUN10:10
Th10: r
in
REAL & (for n be
Nat holds (seq1
. n)
= (r
+ (seq2
. n))) implies (
lim_inf seq1)
= (r
+ (
lim_inf seq2)) & (
lim_sup seq1)
= (r
+ (
lim_sup seq2))
proof
assume that
A1: r
in
REAL and
A2: for n be
Nat holds (seq1
. n)
= (r
+ (seq2
. n));
reconsider R1 = (
rng (
inferior_realsequence seq1)), R2 = (
rng (
inferior_realsequence seq2)), P1 = (
rng (
superior_realsequence seq1)), P2 = (
rng (
superior_realsequence seq2)) as non
empty
Subset of
ExtREAL ;
now
let z be
object;
assume z
in (
{r}
+ R2);
then
consider z2,z3 be
R_eal such that
A3: z
= (z2
+ z3) and
A4: z2
in
{r} and
A5: z3
in R2;
consider n be
object such that
A6: n
in
NAT and
A7: ((
inferior_realsequence seq2)
. n)
= z3 by
A5,
FUNCT_2: 11;
reconsider n as
Element of
NAT by
A6;
consider Y2 be non
empty
Subset of
ExtREAL such that
A8: Y2
= { (seq2
. k) where k be
Nat : n
<= k } and
A9: z3
= (
inf Y2) by
A7,
RINFSUP2:def 6;
consider Y1 be non
empty
Subset of
ExtREAL such that
A10: Y1
= { (seq1
. k) where k be
Nat : n
<= k } and
A11: ((
inferior_realsequence seq1)
. n)
= (
inf Y1) by
RINFSUP2:def 6;
now
let w be
object;
A12: r
in
{r} by
TARSKI:def 1;
assume w
in Y1;
then
consider k1 be
Nat such that
A13: w
= (seq1
. k1) and
A14: n
<= k1 by
A10;
reconsider w1 = w as
R_eal by
A13;
A15: (seq2
. k1)
in Y2 by
A8,
A14;
w1
= (r
+ (seq2
. k1)) by
A2,
A13;
hence w
in (
{r}
+ Y2) by
A12,
A15;
end;
then
A16: Y1
c= (
{r}
+ Y2) by
TARSKI:def 3;
now
let w be
object;
assume w
in (
{r}
+ Y2);
then
consider w1,w2 be
R_eal such that
A17: w
= (w1
+ w2) and
A18: w1
in
{r} and
A19: w2
in Y2;
consider k2 be
Nat such that
A20: w2
= (seq2
. k2) and
A21: n
<= k2 by
A8,
A19;
w1
= r by
A18,
TARSKI:def 1;
then w
= (seq1
. k2) by
A2,
A17,
A20;
hence w
in Y1 by
A10,
A21;
end;
then (
{r}
+ Y2)
c= Y1 by
TARSKI:def 3;
then Y1
= (
{r}
+ Y2) by
A16,
XBOOLE_0:def 10;
then (
inf Y1)
= ((
inf
{r})
+ (
inf Y2)) by
A1,
Th9;
then (
inf Y1)
= (r
+ (
inf Y2)) by
XXREAL_2: 13;
then z
= ((
inferior_realsequence seq1)
. n) by
A4,
A3,
A9,
A11,
TARSKI:def 1;
hence z
in R1 by
FUNCT_2: 4;
end;
then
A22: (
{r}
+ R2)
c= R1 by
TARSKI:def 3;
now
let z be
object;
assume z
in (
{r}
+ P2);
then
consider z2,z3 be
R_eal such that
A23: z
= (z2
+ z3) and
A24: z2
in
{r} and
A25: z3
in P2;
consider n be
object such that
A26: n
in
NAT and
A27: ((
superior_realsequence seq2)
. n)
= z3 by
A25,
FUNCT_2: 11;
reconsider n as
Element of
NAT by
A26;
consider Y2 be non
empty
Subset of
ExtREAL such that
A28: Y2
= { (seq2
. k) where k be
Nat : n
<= k } and
A29: z3
= (
sup Y2) by
A27,
RINFSUP2:def 7;
consider Y1 be non
empty
Subset of
ExtREAL such that
A30: Y1
= { (seq1
. k) where k be
Nat : n
<= k } and
A31: ((
superior_realsequence seq1)
. n)
= (
sup Y1) by
RINFSUP2:def 7;
now
let w be
object;
A32: r
in
{r} by
TARSKI:def 1;
assume w
in Y1;
then
consider k1 be
Nat such that
A33: w
= (seq1
. k1) and
A34: n
<= k1 by
A30;
reconsider w1 = w as
R_eal by
A33;
A35: (seq2
. k1)
in Y2 by
A28,
A34;
w1
= (r
+ (seq2
. k1)) by
A2,
A33;
hence w
in (
{r}
+ Y2) by
A32,
A35;
end;
then
A36: Y1
c= (
{r}
+ Y2) by
TARSKI:def 3;
now
let w be
object;
assume w
in (
{r}
+ Y2);
then
consider w1,w2 be
R_eal such that
A37: w
= (w1
+ w2) and
A38: w1
in
{r} and
A39: w2
in Y2;
consider k2 be
Nat such that
A40: w2
= (seq2
. k2) and
A41: n
<= k2 by
A28,
A39;
w1
= r by
A38,
TARSKI:def 1;
then w
= (seq1
. k2) by
A2,
A37,
A40;
hence w
in Y1 by
A30,
A41;
end;
then (
{r}
+ Y2)
c= Y1 by
TARSKI:def 3;
then Y1
= (
{r}
+ Y2) by
A36,
XBOOLE_0:def 10;
then (
sup Y1)
= ((
sup
{r})
+ (
sup Y2)) by
A1,
Th8;
then (
sup Y1)
= (r
+ (
sup Y2)) by
XXREAL_2: 11;
then z
= ((
superior_realsequence seq1)
. n) by
A24,
A23,
A29,
A31,
TARSKI:def 1;
hence z
in P1 by
FUNCT_2: 4;
end;
then
A42: (
{r}
+ P2)
c= P1 by
TARSKI:def 3;
now
let z be
object;
assume z
in R1;
then
consider n be
object such that
A43: n
in
NAT and
A44: ((
inferior_realsequence seq1)
. n)
= z by
FUNCT_2: 11;
reconsider n as
Element of
NAT by
A43;
consider Y1 be non
empty
Subset of
ExtREAL such that
A45: Y1
= { (seq1
. k) where k be
Nat : n
<= k } and
A46: z
= (
inf Y1) by
A44,
RINFSUP2:def 6;
consider Y2 be non
empty
Subset of
ExtREAL such that
A47: Y2
= { (seq2
. k) where k be
Nat : n
<= k } and
A48: ((
inferior_realsequence seq2)
. n)
= (
inf Y2) by
RINFSUP2:def 6;
now
let w be
object;
A49: r
in
{r} by
TARSKI:def 1;
assume w
in Y1;
then
consider k1 be
Nat such that
A50: w
= (seq1
. k1) and
A51: n
<= k1 by
A45;
reconsider w1 = w as
R_eal by
A50;
A52: (seq2
. k1)
in Y2 by
A47,
A51;
w1
= (r
+ (seq2
. k1)) by
A2,
A50;
hence w
in (
{r}
+ Y2) by
A49,
A52;
end;
then
A53: Y1
c= (
{r}
+ Y2) by
TARSKI:def 3;
now
let w be
object;
assume w
in (
{r}
+ Y2);
then
consider w1,w2 be
R_eal such that
A54: w
= (w1
+ w2) and
A55: w1
in
{r} and
A56: w2
in Y2;
consider k2 be
Nat such that
A57: w2
= (seq2
. k2) and
A58: n
<= k2 by
A47,
A56;
w1
= r by
A55,
TARSKI:def 1;
then w
= (seq1
. k2) by
A2,
A54,
A57;
hence w
in Y1 by
A45,
A58;
end;
then (
{r}
+ Y2)
c= Y1 by
TARSKI:def 3;
then Y1
= (
{r}
+ Y2) by
A53,
XBOOLE_0:def 10;
then (
inf Y1)
= ((
inf
{r})
+ (
inf Y2)) by
A1,
Th9;
then
A59: (
inf Y1)
= (r
+ (
inf Y2)) by
XXREAL_2: 13;
A60: ((
inferior_realsequence seq2)
. n)
in R2 by
FUNCT_2: 4;
r
in
{r} by
TARSKI:def 1;
hence z
in (
{r}
+ R2) by
A46,
A48,
A59,
A60;
end;
then R1
c= (
{r}
+ R2) by
TARSKI:def 3;
then R1
= (
{r}
+ R2) by
A22,
XBOOLE_0:def 10;
then (
sup R1)
= ((
sup
{r})
+ (
sup R2)) by
A1,
Th8;
hence (
lim_inf seq1)
= (r
+ (
lim_inf seq2)) by
XXREAL_2: 11;
now
let z be
object;
assume z
in P1;
then
consider n be
object such that
A61: n
in
NAT and
A62: ((
superior_realsequence seq1)
. n)
= z by
FUNCT_2: 11;
reconsider n as
Element of
NAT by
A61;
consider Y1 be non
empty
Subset of
ExtREAL such that
A63: Y1
= { (seq1
. k) where k be
Nat : n
<= k } and
A64: z
= (
sup Y1) by
A62,
RINFSUP2:def 7;
consider Y2 be non
empty
Subset of
ExtREAL such that
A65: Y2
= { (seq2
. k) where k be
Nat : n
<= k } and
A66: ((
superior_realsequence seq2)
. n)
= (
sup Y2) by
RINFSUP2:def 7;
now
let w be
object;
A67: r
in
{r} by
TARSKI:def 1;
assume w
in Y1;
then
consider k1 be
Nat such that
A68: w
= (seq1
. k1) and
A69: n
<= k1 by
A63;
reconsider w1 = w as
R_eal by
A68;
A70: (seq2
. k1)
in Y2 by
A65,
A69;
w1
= (r
+ (seq2
. k1)) by
A2,
A68;
hence w
in (
{r}
+ Y2) by
A67,
A70;
end;
then
A71: Y1
c= (
{r}
+ Y2) by
TARSKI:def 3;
now
let w be
object;
assume w
in (
{r}
+ Y2);
then
consider w1,w2 be
R_eal such that
A72: w
= (w1
+ w2) and
A73: w1
in
{r} and
A74: w2
in Y2;
consider k2 be
Nat such that
A75: w2
= (seq2
. k2) and
A76: n
<= k2 by
A65,
A74;
w1
= r by
A73,
TARSKI:def 1;
then w
= (seq1
. k2) by
A2,
A72,
A75;
hence w
in Y1 by
A63,
A76;
end;
then (
{r}
+ Y2)
c= Y1 by
TARSKI:def 3;
then Y1
= (
{r}
+ Y2) by
A71,
XBOOLE_0:def 10;
then (
sup Y1)
= ((
sup
{r})
+ (
sup Y2)) by
A1,
Th8;
then
A77: (
sup Y1)
= (r
+ (
sup Y2)) by
XXREAL_2: 11;
A78: ((
superior_realsequence seq2)
. n)
in P2 by
FUNCT_2: 4;
r
in
{r} by
TARSKI:def 1;
hence z
in (
{r}
+ P2) by
A64,
A66,
A77,
A78;
end;
then P1
c= (
{r}
+ P2) by
TARSKI:def 3;
then P1
= (
{r}
+ P2) by
A42,
XBOOLE_0:def 10;
then (
inf P1)
= ((
inf
{r})
+ (
inf P2)) by
A1,
Th9;
hence thesis by
XXREAL_2: 13;
end;
reserve F1,F2 for
Functional_Sequence of X,
ExtREAL ,
f,g,P for
PartFunc of X,
ExtREAL ;
theorem ::
MESFUN10:11
Th11: (
dom (F1
.
0 ))
= (
dom (F2
.
0 )) & F1 is
with_the_same_dom & (f
"
{
+infty })
=
{} & (f
"
{
-infty })
=
{} & (for n be
Nat holds (F1
. n)
= (f
+ (F2
. n))) implies (
lim_inf F1)
= (f
+ (
lim_inf F2)) & (
lim_sup F1)
= (f
+ (
lim_sup F2))
proof
assume that
A1: (
dom (F1
.
0 ))
= (
dom (F2
.
0 )) and
A2: F1 is
with_the_same_dom and
A3: (f
"
{
+infty })
=
{} and
A4: (f
"
{
-infty })
=
{} and
A5: for n be
Nat holds (F1
. n)
= (f
+ (F2
. n));
A6: (F1
.
0 )
= (f
+ (F2
.
0 )) by
A5;
A7: (
dom (f
+ (F2
.
0 )))
= (((
dom f)
/\ (
dom (F2
.
0 )))
\ (((f
"
{
-infty })
/\ ((F2
.
0 )
"
{
+infty }))
\/ ((f
"
{
+infty })
/\ ((F2
.
0 )
"
{
-infty })))) by
MESFUNC1:def 3;
A8: (
dom (f
+ (
lim_sup F2)))
= (((
dom f)
/\ (
dom (
lim_sup F2)))
\ (((f
"
{
-infty })
/\ ((
lim_sup F2)
"
{
+infty }))
\/ ((f
"
{
+infty })
/\ ((
lim_sup F2)
"
{
-infty })))) by
MESFUNC1:def 3;
then
A9: (
dom (f
+ (
lim_sup F2)))
= ((
dom f)
/\ (
dom (F2
.
0 ))) by
A3,
A4,
MESFUNC8:def 8;
then
A10: (
dom (
lim_sup F1))
= (
dom (f
+ (
lim_sup F2))) by
A3,
A4,
A6,
A7,
MESFUNC8:def 8;
A11: (
dom (f
+ (
lim_inf F2)))
= (((
dom f)
/\ (
dom (
lim_inf F2)))
\ (((f
"
{
-infty })
/\ ((
lim_inf F2)
"
{
+infty }))
\/ ((f
"
{
+infty })
/\ ((
lim_inf F2)
"
{
-infty })))) by
MESFUNC1:def 3;
then
A12: (
dom (f
+ (
lim_inf F2)))
= ((
dom f)
/\ (
dom (F2
.
0 ))) by
A3,
A4,
MESFUNC8:def 7;
then
A13: (
dom (
lim_inf F1))
= (
dom (f
+ (
lim_inf F2))) by
A3,
A4,
A6,
A7,
MESFUNC8:def 7;
A14: (
dom (
lim_inf F2))
= (
dom (F2
.
0 )) by
MESFUNC8:def 7;
A15: (
dom (
lim_inf F1))
= (
dom (F1
.
0 )) by
MESFUNC8:def 7;
for x be
Element of X st x
in (
dom (
lim_inf F1)) holds ((
lim_inf F1)
. x)
= ((f
+ (
lim_inf F2))
. x)
proof
let x be
Element of X;
assume
A16: x
in (
dom (
lim_inf F1));
then
A17: ((
lim_inf F1)
. x)
= (
lim_inf (F1
# x)) by
MESFUNC8:def 7;
A18: for n be
Nat holds ((F1
# x)
. n)
= ((f
. x)
+ ((F2
# x)
. n))
proof
let n be
Nat;
(F1
. n)
= (f
+ (F2
. n)) by
A5;
then (
dom (f
+ (F2
. n)))
= (
dom (F1
.
0 )) by
A2,
MESFUNC8:def 2;
then
A19: x
in (
dom (f
+ (F2
. n))) by
A16,
MESFUNC8:def 7;
((F1
. n)
. x)
= ((f
+ (F2
. n))
. x) by
A5;
then ((F1
. n)
. x)
= ((f
. x)
+ ((F2
. n)
. x)) by
A19,
MESFUNC1:def 3;
then ((F1
# x)
. n)
= ((f
. x)
+ ((F2
. n)
. x)) by
MESFUNC5:def 13;
hence thesis by
MESFUNC5:def 13;
end;
A20: (
dom (f
+ (
lim_inf F2)))
c= (
dom f) by
A3,
A4,
A11,
XBOOLE_1: 17;
then not (f
. x)
in
{
-infty } by
A4,
A13,
A16,
FUNCT_1:def 7;
then
A21: (f
. x)
<>
-infty by
TARSKI:def 1;
not (f
. x)
in
{
+infty } by
A3,
A13,
A16,
A20,
FUNCT_1:def 7;
then (f
. x)
<>
+infty by
TARSKI:def 1;
then
A22: (f
. x)
in
REAL by
A21,
XXREAL_0: 14;
x
in (
dom (f
+ (
lim_inf F2))) by
A3,
A4,
A6,
A7,
A12,
A16,
MESFUNC8:def 7;
then
A23: ((f
+ (
lim_inf F2))
. x)
= ((f
. x)
+ ((
lim_inf F2)
. x)) by
MESFUNC1:def 3;
((
lim_inf F2)
. x)
= (
lim_inf (F2
# x)) by
A1,
A15,
A14,
A16,
MESFUNC8:def 7;
hence thesis by
A22,
A18,
A17,
A23,
Th10;
end;
hence (
lim_inf F1)
= (f
+ (
lim_inf F2)) by
A13,
PARTFUN1: 5;
A24: (
dom (
lim_sup F1))
= (
dom (F1
.
0 )) by
MESFUNC8:def 8;
A25: (
dom (
lim_sup F2))
= (
dom (F2
.
0 )) by
MESFUNC8:def 8;
for x be
Element of X st x
in (
dom (
lim_sup F1)) holds ((
lim_sup F1)
. x)
= ((f
+ (
lim_sup F2))
. x)
proof
let x be
Element of X;
assume
A26: x
in (
dom (
lim_sup F1));
then
A27: ((
lim_sup F1)
. x)
= (
lim_sup (F1
# x)) by
MESFUNC8:def 8;
A28: for n be
Nat holds ((F1
# x)
. n)
= ((f
. x)
+ ((F2
# x)
. n))
proof
let n be
Nat;
(F1
. n)
= (f
+ (F2
. n)) by
A5;
then
A29: (
dom (f
+ (F2
. n)))
= (
dom (F1
.
0 )) by
A2,
MESFUNC8:def 2;
((F1
. n)
. x)
= ((f
+ (F2
. n))
. x) by
A5;
then ((F1
. n)
. x)
= ((f
. x)
+ ((F2
. n)
. x)) by
A24,
A26,
A29,
MESFUNC1:def 3;
then ((F1
# x)
. n)
= ((f
. x)
+ ((F2
. n)
. x)) by
MESFUNC5:def 13;
hence thesis by
MESFUNC5:def 13;
end;
A30: (
dom (f
+ (
lim_sup F2)))
c= (
dom f) by
A3,
A4,
A8,
XBOOLE_1: 17;
then not (f
. x)
in
{
-infty } by
A4,
A10,
A26,
FUNCT_1:def 7;
then
A31: (f
. x)
<>
-infty by
TARSKI:def 1;
not (f
. x)
in
{
+infty } by
A3,
A10,
A26,
A30,
FUNCT_1:def 7;
then (f
. x)
<>
+infty by
TARSKI:def 1;
then
A32: (f
. x)
in
REAL by
A31,
XXREAL_0: 14;
x
in (
dom (f
+ (
lim_sup F2))) by
A3,
A4,
A6,
A7,
A9,
A26,
MESFUNC8:def 8;
then
A33: ((f
+ (
lim_sup F2))
. x)
= ((f
. x)
+ ((
lim_sup F2)
. x)) by
MESFUNC1:def 3;
((
lim_sup F2)
. x)
= (
lim_sup (F2
# x)) by
A1,
A24,
A25,
A26,
MESFUNC8:def 8;
hence thesis by
A32,
A28,
A27,
A33,
Th10;
end;
hence thesis by
A10,
PARTFUN1: 5;
end;
reconsider jj = 1 as
Element of
REAL by
XREAL_0:def 1;
theorem ::
MESFUN10:12
Th12: f
is_integrable_on M & g
is_integrable_on M implies (f
- g)
is_integrable_on M
proof
assume that
A1: f
is_integrable_on M and
A2: g
is_integrable_on M;
((
- jj)
(#) g)
is_integrable_on M by
A2,
MESFUNC5: 110;
then (
- g)
is_integrable_on M by
MESFUNC2: 9;
then (f
+ (
- g))
is_integrable_on M by
A1,
MESFUNC5: 108;
hence thesis by
MESFUNC2: 8;
end;
theorem ::
MESFUN10:13
Th13: f
is_integrable_on M & g
is_integrable_on M implies ex E be
Element of S st E
= ((
dom f)
/\ (
dom g)) & (
Integral (M,(f
- g)))
= ((
Integral (M,(f
| E)))
+ (
Integral (M,((
- g)
| E))))
proof
assume that
A1: f
is_integrable_on M and
A2: g
is_integrable_on M;
((
- jj)
(#) g)
is_integrable_on M by
A2,
MESFUNC5: 110;
then (
- g)
is_integrable_on M by
MESFUNC2: 9;
then
consider E be
Element of S such that
A3: E
= ((
dom f)
/\ (
dom (
- g))) and
A4: (
Integral (M,(f
+ (
- g))))
= ((
Integral (M,(f
| E)))
+ (
Integral (M,((
- g)
| E)))) by
A1,
MESFUNC5: 109;
A5: (
dom g)
= (
dom (
- g)) by
MESFUNC1:def 7;
(
Integral (M,(f
- g)))
= ((
Integral (M,(f
| E)))
+ (
Integral (M,((
- g)
| E)))) by
A4,
MESFUNC2: 8;
hence thesis by
A3,
A5;
end;
theorem ::
MESFUN10:14
Th14: (for n be
Nat holds (seq1
. n)
= (
- (seq2
. n))) implies (
lim_inf seq2)
= (
- (
lim_sup seq1)) & (
lim_sup seq2)
= (
- (
lim_inf seq1))
proof
assume
A1: for n be
Nat holds (seq1
. n)
= (
- (seq2
. n));
now
let z be
object;
assume z
in (
rng (
inferior_realsequence seq2));
then
consider n be
object such that
A2: n
in (
dom (
inferior_realsequence seq2)) and
A3: z
= ((
inferior_realsequence seq2)
. n) by
FUNCT_1:def 3;
reconsider n as
Element of
NAT by
A2;
consider R2 be non
empty
Subset of
ExtREAL such that
A4: R2
= { (seq2
. k) where k be
Nat : n
<= k } and
A5: z
= (
inf R2) by
A3,
RINFSUP2:def 6;
reconsider z2 = z as
Element of
ExtREAL by
A3,
XXREAL_0:def 1;
set R1 = { (seq1
. k) where k be
Nat : n
<= k };
reconsider R1 as non
empty
Subset of
ExtREAL by
RINFSUP2: 5;
set z1 = (
- z2);
A6: ex K1 be non
empty
Subset of
ExtREAL st K1
= { (seq1
. k) where k be
Nat : n
<= k } & ((
superior_realsequence seq1)
. n)
= (
sup K1) by
RINFSUP2:def 7;
now
let x be
object;
assume x
in R1;
then
consider k be
Nat such that
A7: x
= (seq1
. k) and
A8: n
<= k;
reconsider x1 = x as
Element of
ExtREAL by
A7;
(
- x1)
= (
- (
- (seq2
. k))) by
A1,
A7;
then (
- x1)
in { (seq2
. k2) where k2 be
Nat : n
<= k2 } by
A8;
then (
- (
- x1))
in (
- R2) by
A4;
hence x
in (
- R2);
end;
then
A9: R1
c= (
- R2) by
TARSKI:def 3;
now
let x be
object;
assume x
in (
- R2);
then
consider y be
R_eal such that
A10: x
= (
- y) and
A11: y
in R2;
consider k be
Nat such that
A12: y
= (seq2
. k) and
A13: n
<= k by
A4,
A11;
(seq1
. k)
= (
- (seq2
. k)) by
A1;
hence x
in R1 by
A10,
A12,
A13;
end;
then (
- R2)
c= R1 by
TARSKI:def 3;
then (
- R2)
= R1 by
A9,
XBOOLE_0:def 10;
then ((
superior_realsequence seq1)
. n)
= z1 by
A5,
A6,
SUPINF_2: 15;
then
A14: z1
in (
rng (
superior_realsequence seq1)) by
FUNCT_2: 4;
z2
= (
- z1);
hence z
in (
- (
rng (
superior_realsequence seq1))) by
A14;
end;
then
A15: (
rng (
inferior_realsequence seq2))
c= (
- (
rng (
superior_realsequence seq1))) by
TARSKI:def 3;
now
let z be
object;
assume z
in (
rng (
superior_realsequence seq2));
then
consider n be
object such that
A16: n
in (
dom (
superior_realsequence seq2)) and
A17: z
= ((
superior_realsequence seq2)
. n) by
FUNCT_1:def 3;
reconsider n as
Element of
NAT by
A16;
consider R2 be non
empty
Subset of
ExtREAL such that
A18: R2
= { (seq2
. k) where k be
Nat : n
<= k } and
A19: z
= (
sup R2) by
A17,
RINFSUP2:def 7;
reconsider z2 = z as
Element of
ExtREAL by
A17,
XXREAL_0:def 1;
set R1 = { (seq1
. k) where k be
Nat : n
<= k };
reconsider R1 as non
empty
Subset of
ExtREAL by
RINFSUP2: 5;
set z1 = (
- z2);
A20: ex K1 be non
empty
Subset of
ExtREAL st K1
= { (seq1
. k) where k be
Nat : n
<= k } & ((
inferior_realsequence seq1)
. n)
= (
inf K1) by
RINFSUP2:def 6;
now
let x be
object;
assume x
in R1;
then
consider k be
Nat such that
A21: x
= (seq1
. k) and
A22: n
<= k;
reconsider x1 = x as
Element of
ExtREAL by
A21;
(
- x1)
= (
- (
- (seq2
. k))) by
A1,
A21;
then (
- x1)
in { (seq2
. k2) where k2 be
Nat : n
<= k2 } by
A22;
then (
- (
- x1))
in (
- R2) by
A18;
hence x
in (
- R2);
end;
then
A23: R1
c= (
- R2) by
TARSKI:def 3;
now
let x be
object;
assume x
in (
- R2);
then
consider y be
R_eal such that
A24: x
= (
- y) and
A25: y
in R2;
consider k be
Nat such that
A26: y
= (seq2
. k) and
A27: n
<= k by
A18,
A25;
(seq1
. k)
= (
- (seq2
. k)) by
A1;
hence x
in R1 by
A24,
A26,
A27;
end;
then (
- R2)
c= R1 by
TARSKI:def 3;
then (
- R2)
= R1 by
A23,
XBOOLE_0:def 10;
then ((
inferior_realsequence seq1)
. n)
= z1 by
A19,
A20,
SUPINF_2: 14;
then
A28: z1
in (
rng (
inferior_realsequence seq1)) by
FUNCT_2: 4;
z2
= (
- z1);
hence z
in (
- (
rng (
inferior_realsequence seq1))) by
A28;
end;
then
A29: (
rng (
superior_realsequence seq2))
c= (
- (
rng (
inferior_realsequence seq1))) by
TARSKI:def 3;
now
let z be
object;
assume z
in (
- (
rng (
superior_realsequence seq1)));
then
consider t be
R_eal such that
A30: z
= (
- t) and
A31: t
in (
rng (
superior_realsequence seq1));
consider n be
object such that
A32: n
in (
dom (
superior_realsequence seq1)) and
A33: t
= ((
superior_realsequence seq1)
. n) by
A31,
FUNCT_1:def 3;
reconsider n as
Element of
NAT by
A32;
consider R1 be non
empty
Subset of
ExtREAL such that
A34: R1
= { (seq1
. k) where k be
Nat : n
<= k } and
A35: t
= (
sup R1) by
A33,
RINFSUP2:def 7;
reconsider z1 = z as
Element of
ExtREAL by
A30;
set R2 = { (seq2
. k) where k be
Nat : n
<= k };
reconsider R2 as non
empty
Subset of
ExtREAL by
RINFSUP2: 5;
A36: ex K2 be non
empty
Subset of
ExtREAL st K2
= { (seq2
. k) where k be
Nat : n
<= k } & ((
inferior_realsequence seq2)
. n)
= (
inf K2) by
RINFSUP2:def 6;
now
let x be
object;
assume x
in R2;
then
consider k be
Nat such that
A37: x
= (seq2
. k) and
A38: n
<= k;
reconsider x1 = x as
Element of
ExtREAL by
A37;
(
- x1)
= (
- (
- (seq1
. k))) by
A1,
A37;
then (
- x1)
in { (seq1
. k2) where k2 be
Nat : n
<= k2 } by
A38;
then (
- (
- x1))
in (
- R1) by
A34;
hence x
in (
- R1);
end;
then
A39: R2
c= (
- R1) by
TARSKI:def 3;
now
let x be
object;
assume x
in (
- R1);
then
consider y be
R_eal such that
A40: x
= (
- y) and
A41: y
in R1;
consider k be
Nat such that
A42: y
= (seq1
. k) and
A43: n
<= k by
A34,
A41;
(seq1
. k)
= (
- (seq2
. k)) by
A1;
hence x
in R2 by
A40,
A42,
A43;
end;
then (
- R1)
c= R2 by
TARSKI:def 3;
then (
- R1)
= R2 by
A39,
XBOOLE_0:def 10;
then ((
inferior_realsequence seq2)
. n)
= z1 by
A30,
A35,
A36,
SUPINF_2: 14;
hence z
in (
rng (
inferior_realsequence seq2)) by
FUNCT_2: 4;
end;
then (
- (
rng (
superior_realsequence seq1)))
c= (
rng (
inferior_realsequence seq2)) by
TARSKI:def 3;
then (
rng (
inferior_realsequence seq2))
= (
- (
rng (
superior_realsequence seq1))) by
A15,
XBOOLE_0:def 10;
hence (
lim_inf seq2)
= (
- (
lim_sup seq1)) by
SUPINF_2: 15;
now
let z be
object;
assume z
in (
- (
rng (
inferior_realsequence seq1)));
then
consider t be
R_eal such that
A44: z
= (
- t) and
A45: t
in (
rng (
inferior_realsequence seq1));
consider n be
object such that
A46: n
in (
dom (
inferior_realsequence seq1)) and
A47: t
= ((
inferior_realsequence seq1)
. n) by
A45,
FUNCT_1:def 3;
reconsider n as
Element of
NAT by
A46;
consider R1 be non
empty
Subset of
ExtREAL such that
A48: R1
= { (seq1
. k) where k be
Nat : n
<= k } and
A49: t
= (
inf R1) by
A47,
RINFSUP2:def 6;
reconsider z1 = z as
Element of
ExtREAL by
A44;
set R2 = { (seq2
. k) where k be
Nat : n
<= k };
reconsider R2 as non
empty
Subset of
ExtREAL by
RINFSUP2: 5;
A50: ex K2 be non
empty
Subset of
ExtREAL st K2
= { (seq2
. k) where k be
Nat : n
<= k } & ((
superior_realsequence seq2)
. n)
= (
sup K2) by
RINFSUP2:def 7;
now
let x be
object;
assume x
in R2;
then
consider k be
Nat such that
A51: x
= (seq2
. k) and
A52: n
<= k;
reconsider x1 = x as
Element of
ExtREAL by
A51;
(seq1
. k)
= (
- (seq2
. k)) by
A1;
then (
- x1)
in R1 by
A48,
A51,
A52;
then (
- (
- x1))
in (
- R1);
hence x
in (
- R1);
end;
then
A53: R2
c= (
- R1) by
TARSKI:def 3;
now
let x be
object;
assume x
in (
- R1);
then
consider y be
R_eal such that
A54: x
= (
- y) and
A55: y
in R1;
consider k be
Nat such that
A56: y
= (seq1
. k) and
A57: n
<= k by
A48,
A55;
(seq1
. k)
= (
- (seq2
. k)) by
A1;
hence x
in R2 by
A54,
A56,
A57;
end;
then (
- R1)
c= R2 by
TARSKI:def 3;
then (
- R1)
= R2 by
A53,
XBOOLE_0:def 10;
then ((
superior_realsequence seq2)
. n)
= z1 by
A44,
A49,
A50,
SUPINF_2: 15;
hence z
in (
rng (
superior_realsequence seq2)) by
FUNCT_2: 4;
end;
then (
- (
rng (
inferior_realsequence seq1)))
c= (
rng (
superior_realsequence seq2)) by
TARSKI:def 3;
then (
rng (
superior_realsequence seq2))
= (
- (
rng (
inferior_realsequence seq1))) by
A29,
XBOOLE_0:def 10;
hence thesis by
SUPINF_2: 14;
end;
theorem ::
MESFUN10:15
Th15: (
dom (F1
.
0 ))
= (
dom (F2
.
0 )) & F1 is
with_the_same_dom & (for n be
Nat holds (F1
. n)
= (
- (F2
. n))) implies (
lim_inf F1)
= (
- (
lim_sup F2)) & (
lim_sup F1)
= (
- (
lim_inf F2))
proof
assume that
A1: (
dom (F1
.
0 ))
= (
dom (F2
.
0 )) and
A2: F1 is
with_the_same_dom and
A3: for n be
Nat holds (F1
. n)
= (
- (F2
. n));
A4: (
dom (
lim_inf F1))
= (
dom (F1
.
0 )) by
MESFUNC8:def 7;
A5: (
dom (
lim_sup F2))
= (
dom (F2
.
0 )) by
MESFUNC8:def 8;
A6:
now
let x be
Element of X;
assume
A7: x
in (
dom (F1
.
0 ));
let n be
Nat;
(
dom (F1
. n))
= (
dom (F1
.
0 )) by
A2,
MESFUNC8:def 2;
then
A8: x
in (
dom (
- (F2
. n))) by
A3,
A7;
((F1
. n)
. x)
= ((
- (F2
. n))
. x) by
A3;
then ((F1
. n)
. x)
= (
- ((F2
. n)
. x)) by
A8,
MESFUNC1:def 7;
then ((F1
# x)
. n)
= (
- ((F2
. n)
. x)) by
MESFUNC5:def 13;
hence ((F2
# x)
. n)
= (
- ((F1
# x)
. n)) by
MESFUNC5:def 13;
end;
A9:
now
let x be
Element of X;
assume
A10: x
in (
dom (
lim_inf F1));
then
A11: ((
lim_inf F1)
. x)
= (
lim_inf (F1
# x)) by
MESFUNC8:def 7;
x
in (
dom (
- (
lim_sup F2))) by
A1,
A4,
A5,
A10,
MESFUNC1:def 7;
then
A12: ((
- (
lim_sup F2))
. x)
= (
- ((
lim_sup F2)
. x)) by
MESFUNC1:def 7;
A13: for n be
Nat holds ((F2
# x)
. n)
= (
- ((F1
# x)
. n)) by
A4,
A6,
A10;
((
lim_sup F2)
. x)
= (
lim_sup (F2
# x)) by
A1,
A4,
A5,
A10,
MESFUNC8:def 8;
hence ((
lim_inf F1)
. x)
= ((
- (
lim_sup F2))
. x) by
A13,
A11,
A12,
Th14;
end;
(
dom (
- (
lim_sup F2)))
= (
dom (
lim_sup F2)) by
MESFUNC1:def 7;
hence (
lim_inf F1)
= (
- (
lim_sup F2)) by
A1,
A4,
A5,
A9,
PARTFUN1: 5;
A14: (
dom (
lim_sup F1))
= (
dom (F1
.
0 )) by
MESFUNC8:def 8;
A15: (
dom (
lim_inf F2))
= (
dom (F2
.
0 )) by
MESFUNC8:def 7;
A16: for x be
Element of X st x
in (
dom (
lim_sup F1)) holds ((
lim_sup F1)
. x)
= ((
- (
lim_inf F2))
. x)
proof
let x be
Element of X;
assume
A17: x
in (
dom (
lim_sup F1));
then
A18: ((
lim_sup F1)
. x)
= (
lim_sup (F1
# x)) by
MESFUNC8:def 8;
x
in (
dom (
- (
lim_inf F2))) by
A1,
A14,
A15,
A17,
MESFUNC1:def 7;
then
A19: ((
- (
lim_inf F2))
. x)
= (
- ((
lim_inf F2)
. x)) by
MESFUNC1:def 7;
A20: for n be
Nat holds ((F2
# x)
. n)
= (
- ((F1
# x)
. n)) by
A14,
A6,
A17;
((
lim_inf F2)
. x)
= (
lim_inf (F2
# x)) by
A1,
A14,
A15,
A17,
MESFUNC8:def 7;
hence thesis by
A20,
A18,
A19,
Th14;
end;
(
dom (
- (
lim_inf F2)))
= (
dom (
lim_inf F2)) by
MESFUNC1:def 7;
hence thesis by
A1,
A14,
A15,
A16,
PARTFUN1: 5;
end;
theorem ::
MESFUN10:16
Th16: E
= (
dom (F
.
0 )) & E
= (
dom P) & (for n be
Nat holds (F
. n) is E
-measurable) & P
is_integrable_on M & (for x be
Element of X, n be
Nat st x
in E holds (
|.(F
. n).|
. x)
<= (P
. x)) implies (for n be
Nat holds
|.(F
. n).|
is_integrable_on M) &
|.(
lim_inf F).|
is_integrable_on M &
|.(
lim_sup F).|
is_integrable_on M
proof
assume that
A1: E
= (
dom (F
.
0 )) and
A2: E
= (
dom P) and
A3: for n be
Nat holds (F
. n) is E
-measurable and
A4: P
is_integrable_on M and
A5: for x be
Element of X, n be
Nat st x
in E holds (
|.(F
. n).|
. x)
<= (P
. x);
A6: (
lim_inf F) is E
-measurable by
A1,
A3,
MESFUNC8: 24;
hereby
let n be
Nat;
A7: (F
. n) is E
-measurable by
A3;
A8: E
= (
dom (F
. n)) by
A1,
MESFUNC8:def 2;
now
let x be
Element of X;
assume
A9: x
in (
dom (F
. n));
then
A10: x
in (
dom
|.(F
. n).|) by
MESFUNC1:def 10;
(
|.(F
. n).|
. x)
<= (P
. x) by
A5,
A8,
A9;
hence
|.((F
. n)
. x).|
<= (P
. x) by
A10,
MESFUNC1:def 10;
end;
then (F
. n)
is_integrable_on M by
A2,
A4,
A8,
A7,
MESFUNC5: 102;
hence
|.(F
. n).|
is_integrable_on M by
MESFUNC5: 100;
end;
A11: E
= (
dom (
lim_inf F)) by
A1,
MESFUNC8:def 7;
A12: (
lim_sup F) is E
-measurable by
A1,
A3,
MESFUNC8: 23;
A13: for x be
Element of X, k be
Nat st x
in E holds (
- (P
. x))
<= ((F
# x)
. k) & ((F
# x)
. k)
<= (P
. x)
proof
let x be
Element of X, k be
Nat;
assume
A14: x
in E;
then x
in (
dom (F
. k)) by
A1,
MESFUNC8:def 2;
then
A15: x
in (
dom
|.(F
. k).|) by
MESFUNC1:def 10;
(
|.(F
. k).|
. x)
<= (P
. x) by
A5,
A14;
then
A16:
|.((F
. k)
. x).|
<= (P
. x) by
A15,
MESFUNC1:def 10;
then
A17: ((F
. k)
. x)
<= (P
. x) by
EXTREAL1: 23;
(
- (P
. x))
<= ((F
. k)
. x) by
A16,
EXTREAL1: 23;
hence thesis by
A17,
MESFUNC5:def 13;
end;
now
let x be
Element of X;
assume
A18: x
in (
dom (
lim_inf F));
then
A19: x
in E by
A1,
MESFUNC8:def 7;
for k be
Nat holds ((
inferior_realsequence (F
# x))
. k)
<= (P
. x)
proof
let k be
Nat;
reconsider k1 = k as
Nat;
A20: ((
inferior_realsequence (F
# x))
. k1)
<= ((F
# x)
. k1) by
RINFSUP2: 8;
((F
# x)
. k)
<= (P
. x) by
A13,
A19;
hence thesis by
A20,
XXREAL_0: 2;
end;
then (
lim_inf (F
# x))
<= (P
. x) by
Th5;
then
A21: ((
lim_inf F)
. x)
<= (P
. x) by
A18,
MESFUNC8:def 7;
now
let y be
ExtReal;
assume y
in (
rng (F
# x));
then ex k be
object st k
in (
dom (F
# x)) & y
= ((F
# x)
. k) by
FUNCT_1:def 3;
hence (
- (P
. x))
<= y by
A13,
A19;
end;
then (
- (P
. x)) is
LowerBound of (
rng (F
# x)) by
XXREAL_2:def 2;
then (
- (P
. x))
<= (
inf (F
# x)) by
XXREAL_2:def 4;
then (
- (P
. x))
<= (
inf ((F
# x)
^\
0 )) by
NAT_1: 47;
then
A22: (
- (P
. x))
<= ((
inferior_realsequence (F
# x))
.
0 ) by
RINFSUP2: 27;
((
inferior_realsequence (F
# x))
.
0 )
<= (
sup (
inferior_realsequence (F
# x))) by
RINFSUP2: 23;
then (
- (P
. x))
<= (
lim_inf (F
# x)) by
A22,
XXREAL_0: 2;
then (
- (P
. x))
<= ((
lim_inf F)
. x) by
A18,
MESFUNC8:def 7;
hence
|.((
lim_inf F)
. x).|
<= (P
. x) by
A21,
EXTREAL1: 23;
end;
then (
lim_inf F)
is_integrable_on M by
A2,
A4,
A11,
A6,
MESFUNC5: 102;
hence
|.(
lim_inf F).|
is_integrable_on M by
MESFUNC5: 100;
A23: E
= (
dom (
lim_sup F)) by
A1,
MESFUNC8:def 8;
now
let x be
Element of X;
assume
A24: x
in (
dom (
lim_sup F));
for k be
Nat holds ((
superior_realsequence (F
# x))
. k)
>= (
- (P
. x))
proof
let k be
Nat;
reconsider k1 = k as
Nat;
A25: ((
superior_realsequence (F
# x))
. k1)
>= ((F
# x)
. k1) by
RINFSUP2: 8;
((F
# x)
. k)
>= (
- (P
. x)) by
A23,
A13,
A24;
hence thesis by
A25,
XXREAL_0: 2;
end;
then (
lim_sup (F
# x))
>= (
- (P
. x)) by
Th4;
then
A26: ((
lim_sup F)
. x)
>= (
- (P
. x)) by
A24,
MESFUNC8:def 8;
now
let y be
ExtReal;
assume y
in (
rng (F
# x));
then ex k be
object st k
in (
dom (F
# x)) & y
= ((F
# x)
. k) by
FUNCT_1:def 3;
hence (P
. x)
>= y by
A23,
A13,
A24;
end;
then (P
. x) is
UpperBound of (
rng (F
# x)) by
XXREAL_2:def 1;
then (P
. x)
>= (
sup (
rng (F
# x))) by
XXREAL_2:def 3;
then (P
. x)
>= (
sup ((F
# x)
^\
0 )) by
NAT_1: 47;
then
A27: (P
. x)
>= ((
superior_realsequence (F
# x))
.
0 ) by
RINFSUP2: 27;
((
superior_realsequence (F
# x))
.
0 )
>= (
inf (
superior_realsequence (F
# x))) by
RINFSUP2: 23;
then (P
. x)
>= (
lim_sup (F
# x)) by
A27,
XXREAL_0: 2;
then (P
. x)
>= ((
lim_sup F)
. x) by
A24,
MESFUNC8:def 8;
hence
|.((
lim_sup F)
. x).|
<= (P
. x) by
A26,
EXTREAL1: 23;
end;
then (
lim_sup F)
is_integrable_on M by
A2,
A4,
A23,
A12,
MESFUNC5: 102;
hence thesis by
MESFUNC5: 100;
end;
Lm1: E
= (
dom (F
.
0 )) & E
= (
dom P) & (for n be
Nat holds (F
. n) is E
-measurable) & P
is_integrable_on M & P is
nonnegative & (for x be
Element of X, n be
Nat st x
in E holds (
|.(F
. n).|
. x)
<= (P
. x)) & (
eq_dom (P,
+infty ))
=
{} implies ex I be
ExtREAL_sequence st (for n be
Nat holds (I
. n)
= (
Integral (M,(F
. n)))) & (
lim_inf I)
>= (
Integral (M,(
lim_inf F))) & (
lim_sup I)
<= (
Integral (M,(
lim_sup F))) & ((for x be
Element of X st x
in E holds (F
# x) is
convergent) implies I is
convergent & (
lim I)
= (
Integral (M,(
lim F))))
proof
assume that
A1: E
= (
dom (F
.
0 )) and
A2: E
= (
dom P) and
A3: for n be
Nat holds (F
. n) is E
-measurable and
A4: P
is_integrable_on M and
A5: P is
nonnegative and
A6: for x be
Element of X, n be
Nat st x
in E holds (
|.(F
. n).|
. x)
<= (P
. x) and
A7: (
eq_dom (P,
+infty ))
=
{} ;
A8: E
= (
dom (
lim_inf F)) by
A1,
MESFUNC8:def 7;
then
A9: ((
lim_inf F)
| E)
= (
lim_inf F) by
RELAT_1: 68;
deffunc
G(
Nat) = (P
+ (F
. $1));
consider G be
Function such that
A10: (
dom G)
=
NAT & for n be
Element of
NAT holds (G
. n)
=
G(n) from
FUNCT_1:sch 4;
A11: for x be
Element of X, k be
Nat st x
in E holds (
- (P
. x))
<= ((F
# x)
. k) & ((F
# x)
. k)
<= (P
. x)
proof
let x be
Element of X, k be
Nat;
assume
A12: x
in E;
then x
in (
dom (F
. k)) by
A1,
MESFUNC8:def 2;
then
A13: x
in (
dom
|.(F
. k).|) by
MESFUNC1:def 10;
(
|.(F
. k).|
. x)
<= (P
. x) by
A6,
A12;
then
A14:
|.((F
. k)
. x).|
<= (P
. x) by
A13,
MESFUNC1:def 10;
then
A15: ((F
. k)
. x)
<= (P
. x) by
EXTREAL1: 23;
(
- (P
. x))
<= ((F
. k)
. x) by
A14,
EXTREAL1: 23;
hence thesis by
A15,
MESFUNC5:def 13;
end;
A16:
now
let x be
Element of X;
assume
A17: x
in (
dom (
lim_inf F));
now
let k be
Nat;
A18: ((
inferior_realsequence (F
# x))
. k)
<= ((F
# x)
. k) by
RINFSUP2: 8;
((F
# x)
. k)
<= (P
. x) by
A8,
A11,
A17;
hence ((
inferior_realsequence (F
# x))
. k)
<= (P
. x) by
A18,
XXREAL_0: 2;
end;
then (
lim_inf (F
# x))
<= (P
. x) by
Th5;
then
A19: ((
lim_inf F)
. x)
<= (P
. x) by
A17,
MESFUNC8:def 7;
now
let y be
ExtReal;
assume y
in (
rng (F
# x));
then ex k be
object st k
in (
dom (F
# x)) & y
= ((F
# x)
. k) by
FUNCT_1:def 3;
hence (
- (P
. x))
<= y by
A8,
A11,
A17;
end;
then (
- (P
. x)) is
LowerBound of (
rng (F
# x)) by
XXREAL_2:def 2;
then (
- (P
. x))
<= (
inf (
rng (F
# x))) by
XXREAL_2:def 4;
then (
- (P
. x))
<= (
inf ((F
# x)
^\
0 )) by
NAT_1: 47;
then
A20: (
- (P
. x))
<= ((
inferior_realsequence (F
# x))
.
0 ) by
RINFSUP2: 27;
((
inferior_realsequence (F
# x))
.
0 )
<= (
sup (
inferior_realsequence (F
# x))) by
RINFSUP2: 23;
then (
- (P
. x))
<= (
lim_inf (F
# x)) by
A20,
XXREAL_0: 2;
then (
- (P
. x))
<= ((
lim_inf F)
. x) by
A17,
MESFUNC8:def 7;
hence
|.((
lim_inf F)
. x).|
<= (P
. x) by
A19,
EXTREAL1: 23;
end;
(
lim_inf F) is E
-measurable by
A1,
A3,
MESFUNC8: 24;
then (
lim_inf F)
is_integrable_on M by
A2,
A4,
A8,
A16,
MESFUNC5: 102;
then
A21: ex E3 be
Element of S st E3
= ((
dom P)
/\ (
dom (
lim_inf F))) & (
Integral (M,(P
+ (
lim_inf F))))
= ((
Integral (M,(P
| E3)))
+ (
Integral (M,((
lim_inf F)
| E3)))) by
A4,
MESFUNC5: 109;
A22: (P
| E)
= P by
A2,
RELAT_1: 68;
A23: (
Integral (M,P))
<
+infty by
A4,
MESFUNC5: 96;
-infty
< (
Integral (M,P)) by
A4,
MESFUNC5: 96;
then
A24: (
Integral (M,P)) is
Element of
REAL by
A23,
XXREAL_0: 14;
now
let x be
object;
assume x
in (P
"
{
-infty });
then
A25: (P
. x)
in
{
-infty } by
FUNCT_1:def 7;
0
<= (P
. x) by
A5,
SUPINF_2: 51;
hence contradiction by
A25,
TARSKI:def 1;
end;
then
A26: (P
"
{
-infty })
=
{} by
XBOOLE_0:def 1;
A27:
now
let n be
Nat;
n
in
NAT by
ORDINAL1:def 12;
then (G
. n)
= (P
+ (F
. n)) by
A10;
hence (G
. n) is
PartFunc of X,
ExtREAL ;
end;
A28:
now
let n be
Nat;
n
in
NAT by
ORDINAL1:def 12;
hence (G
. n)
= (P
+ (F
. n)) by
A10;
end;
reconsider G as
Functional_Sequence of X,
ExtREAL by
A10,
A27,
SEQFUNC: 1;
A29: (P
"
{
+infty })
=
{} by
A7,
MESFUNC5: 30;
A30: for n be
Nat holds (
dom (G
. n))
= E
proof
let n be
Nat;
(
dom (G
. n))
= (
dom (P
+ (F
. n))) by
A28;
then
A31: (
dom (G
. n))
= (((
dom P)
/\ (
dom (F
. n)))
\ (((P
"
{
-infty })
/\ ((F
. n)
"
{
+infty }))
\/ ((P
"
{
+infty })
/\ ((F
. n)
"
{
-infty })))) by
MESFUNC1:def 3;
(
dom (F
. n))
= E by
A1,
MESFUNC8:def 2;
hence thesis by
A2,
A29,
A26,
A31;
end;
A32:
now
let n,m be
Nat;
thus (
dom (G
. n))
= E by
A30
.= (
dom (G
. m)) by
A30;
end;
deffunc
H(
Nat) = (P
- (F
. $1));
consider H be
Function such that
A33: (
dom H)
=
NAT & for n be
Element of
NAT holds (H
. n)
=
H(n) from
FUNCT_1:sch 4;
reconsider G as
with_the_same_dom
Functional_Sequence of X,
ExtREAL by
A32,
MESFUNC8:def 2;
A34: (
dom (G
.
0 ))
= (
dom (F
.
0 )) by
A1,
A30;
A35: for n be
Nat holds (F
. n)
is_integrable_on M
proof
let n be
Nat;
A36: E
= (
dom (F
. n)) by
A1,
MESFUNC8:def 2;
A37:
now
let x be
Element of X;
assume
A38: x
in (
dom (F
. n));
then
A39: x
in (
dom
|.(F
. n).|) by
MESFUNC1:def 10;
(
|.(F
. n).|
. x)
<= (P
. x) by
A6,
A36,
A38;
hence
|.((F
. n)
. x).|
<= (P
. x) by
A39,
MESFUNC1:def 10;
end;
(F
. n) is E
-measurable by
A3;
hence thesis by
A2,
A4,
A36,
A37,
MESFUNC5: 102;
end;
A40:
now
let n be
Nat;
A41: (G
. n)
= (P
+ (F
. n)) by
A28;
now
let x be
object;
assume
A42: x
in (
dom (P
+ (F
. n)));
then
reconsider x1 = x as
Element of X;
x
in E by
A30,
A41,
A42;
then (
- (P
. x))
<= ((F
# x1)
. n) by
A11;
then
A43: (
- (P
. x))
<= ((F
. n)
. x) by
MESFUNC5:def 13;
((
- (P
. x))
+ (P
. x))
=
0 by
XXREAL_3: 7;
then
0
<= (((F
. n)
. x)
+ (P
. x)) by
A43,
XXREAL_3: 36;
hence
0
<= ((P
+ (F
. n))
. x) by
A42,
MESFUNC1:def 3;
end;
hence (G
. n) is
nonnegative by
A41,
SUPINF_2: 52;
(F
. n)
is_integrable_on M by
A35;
then (G
. n)
is_integrable_on M by
A4,
A41,
MESFUNC5: 108;
then
consider E1 be
Element of S such that
AB: E1
= (
dom (G
. n)) & (G
. n) is E1
-measurable;
for r be
Real holds (E
/\ (
less_dom ((G
. n),r)))
in S
proof
let r be
Real;
AC: (E1
/\ (
less_dom ((G
. n),r)))
in S by
AB;
E
= E1 by
A30,
AB;
hence thesis by
AC;
end;
hence (G
. n) is E
-measurable;
end;
E
= (
dom (G
.
0 )) by
A30;
then
consider IG be
ExtREAL_sequence such that
A44: for n be
Nat holds (IG
. n)
= (
Integral (M,(G
. n))) and
A45: (
Integral (M,(
lim_inf G)))
<= (
lim_inf IG) by
A40,
Th7;
A46: (
Integral (M,P))
<
+infty by
A4,
MESFUNC5: 96;
deffunc
I(
Nat) = (
Integral (M,(F
. $1)));
consider I be
sequence of
ExtREAL such that
A47: for n be
Element of
NAT holds (I
. n)
=
I(n) from
FUNCT_2:sch 4;
reconsider I as
ExtREAL_sequence;
A48:
-infty
< (
Integral (M,P)) by
A4,
MESFUNC5: 96;
A49: for n be
Nat holds (I
. n)
= (
Integral (M,(F
. n))) & (I
. n)
in
REAL
proof
let n be
Nat;
n
in
NAT by
ORDINAL1:def 12;
then
A50: (I
. n)
= (
Integral (M,(F
. n))) by
A47;
A51: (F
. n)
is_integrable_on M by
A35;
then
A52: (
Integral (M,(F
. n)))
<
+infty by
MESFUNC5: 96;
-infty
< (
Integral (M,(F
. n))) by
A51,
MESFUNC5: 96;
hence thesis by
A50,
A52,
XXREAL_0: 14;
end;
now
let n be
Nat;
A53: (G
. n)
= (P
+ (F
. n)) by
A28;
(F
. n)
is_integrable_on M by
A35;
then
A54: ex E2 be
Element of S st E2
= ((
dom P)
/\ (
dom (F
. n))) & (
Integral (M,(G
. n)))
= ((
Integral (M,(P
| E2)))
+ (
Integral (M,((F
. n)
| E2)))) by
A4,
A53,
MESFUNC5: 109;
A55: (P
| E)
= P by
A2,
RELAT_1: 68;
A56: (
dom (F
. n))
= E by
A1,
MESFUNC8:def 2;
then ((F
. n)
| E)
= (F
. n) by
RELAT_1: 68;
then (
Integral (M,(G
. n)))
= ((
Integral (M,P))
+ (I
. n)) by
A2,
A49,
A54,
A56,
A55;
hence (IG
. n)
= ((
Integral (M,P))
+ (I
. n)) by
A44;
end;
then (
lim_inf IG)
= ((
Integral (M,P))
+ (
lim_inf I)) by
A24,
Th10;
then ((
Integral (M,P))
+ (
Integral (M,(
lim_inf F))))
<= ((
Integral (M,P))
+ (
lim_inf I)) by
A2,
A8,
A28,
A29,
A26,
A45,
A21,
A22,
A9,
A34,
Th11;
then (
Integral (M,(
lim_inf F)))
<= (((
lim_inf I)
+ (
Integral (M,P)))
- (
Integral (M,P))) by
A48,
A46,
XXREAL_3: 56;
then (
Integral (M,(
lim_inf F)))
<= ((
lim_inf I)
+ ((
Integral (M,P))
- (
Integral (M,P)))) by
A48,
A46,
XXREAL_3: 30;
then (
Integral (M,(
lim_inf F)))
<= ((
lim_inf I)
+
0. ) by
XXREAL_3: 7;
then
A57: (
Integral (M,(
lim_inf F)))
<= (
lim_inf I) by
XXREAL_3: 4;
A58:
now
let n be
Nat;
A59: n
in
NAT by
ORDINAL1:def 12;
(H
. n)
= (P
- (F
. n)) by
A33,
A59;
hence (H
. n) is
PartFunc of X,
ExtREAL ;
end;
A60:
now
let n be
Nat;
n
in
NAT by
ORDINAL1:def 12;
hence (H
. n)
= (P
- (F
. n)) by
A33;
end;
A61: E
= (
dom (
lim_sup F)) by
A1,
MESFUNC8:def 8;
A62:
now
let x be
Element of X;
assume
A63: x
in (
dom (
lim_sup F));
for k be
Nat holds ((
superior_realsequence (F
# x))
. k)
>= (
- (P
. x))
proof
let k be
Nat;
A64: ((
superior_realsequence (F
# x))
. k)
>= ((F
# x)
. k) by
RINFSUP2: 8;
((F
# x)
. k)
>= (
- (P
. x)) by
A61,
A11,
A63;
hence thesis by
A64,
XXREAL_0: 2;
end;
then (
lim_sup (F
# x))
>= (
- (P
. x)) by
Th4;
then
A65: ((
lim_sup F)
. x)
>= (
- (P
. x)) by
A63,
MESFUNC8:def 8;
now
let y be
ExtReal;
assume y
in (
rng (F
# x));
then ex k be
object st k
in (
dom (F
# x)) & y
= ((F
# x)
. k) by
FUNCT_1:def 3;
hence (P
. x)
>= y by
A61,
A11,
A63;
end;
then (P
. x) is
UpperBound of (
rng (F
# x)) by
XXREAL_2:def 1;
then (P
. x)
>= (
sup (
rng (F
# x))) by
XXREAL_2:def 3;
then (P
. x)
>= (
sup ((F
# x)
^\
0 )) by
NAT_1: 47;
then
A66: (P
. x)
>= ((
superior_realsequence (F
# x))
.
0 ) by
RINFSUP2: 27;
((
superior_realsequence (F
# x))
.
0 )
>= (
inf (
superior_realsequence (F
# x))) by
RINFSUP2: 23;
then (P
. x)
>= (
lim_sup (F
# x)) by
A66,
XXREAL_0: 2;
then (P
. x)
>= ((
lim_sup F)
. x) by
A63,
MESFUNC8:def 8;
hence
|.((
lim_sup F)
. x).|
<= (P
. x) by
A65,
EXTREAL1: 23;
end;
(
lim_sup F) is E
-measurable by
A1,
A3,
MESFUNC8: 23;
then
A67: (
lim_sup F)
is_integrable_on M by
A2,
A4,
A61,
A62,
MESFUNC5: 102;
then
A68: ex E6 be
Element of S st E6
= ((
dom P)
/\ (
dom (
lim_sup F))) & (
Integral (M,(P
- (
lim_sup F))))
= ((
Integral (M,(P
| E6)))
+ (
Integral (M,((
- (
lim_sup F))
| E6)))) by
A4,
Th13;
set E1 = (
Integral (M,(
lim_sup F)));
A69: E1
<
+infty by
A67,
MESFUNC5: 96;
-infty
< E1 by
A67,
MESFUNC5: 96;
then
reconsider e1 = E1 as
Element of
REAL by
A69,
XXREAL_0: 14;
A70: (
- E1)
= (
- e1) by
SUPINF_2: 2;
A71: (P
| E)
= P by
A2,
RELAT_1: 68;
deffunc
F1(
Nat) = (
- (F
. $1));
consider F1 be
Function such that
A72: (
dom F1)
=
NAT & for n be
Element of
NAT holds (F1
. n)
=
F1(n) from
FUNCT_1:sch 4;
reconsider H as
Functional_Sequence of X,
ExtREAL by
A33,
A58,
SEQFUNC: 1;
A73:
now
let n be
Nat;
A74: (
dom (H
. n))
= (
dom (P
- (F
. n))) by
A60;
(
dom (F
. n))
= E by
A1,
MESFUNC8:def 2;
then (
dom (H
. n))
= ((E
/\ E)
\ ((
{}
/\ ((F
. n)
"
{
+infty }))
\/ (
{}
/\ ((F
. n)
"
{
-infty })))) by
A2,
A29,
A26,
A74,
MESFUNC1:def 4;
hence (
dom (H
. n))
= E;
end;
now
let n,m be
Nat;
thus (
dom (H
. n))
= E by
A73
.= (
dom (H
. m)) by
A73;
end;
then
reconsider H as
with_the_same_dom
Functional_Sequence of X,
ExtREAL by
MESFUNC8:def 2;
A75:
-infty
< (
Integral (M,P)) by
A4,
MESFUNC5: 96;
A76:
now
let n be
Nat;
A77: (H
. n)
= (P
- (F
. n)) by
A60;
now
let x be
Element of X;
assume x
in (
dom (F
. n));
then x
in E by
A1,
MESFUNC8:def 2;
then ((F
# x)
. n)
<= (P
. x) by
A11;
hence ((F
. n)
. x)
<= (P
. x) by
MESFUNC5:def 13;
end;
hence (H
. n) is
nonnegative by
A77,
MESFUNC7: 1;
(F
. n)
is_integrable_on M by
A35;
then (H
. n)
is_integrable_on M by
A4,
A77,
Th12;
then
consider E4 be
Element of S such that
AA: E4
= (
dom (H
. n)) & (H
. n) is E4
-measurable;
E4
= E by
AA,
A73;
hence (H
. n) is E
-measurable by
AA;
end;
E
= (
dom (H
.
0 )) by
A73;
then
consider IH be
ExtREAL_sequence such that
A78: for n be
Nat holds (IH
. n)
= (
Integral (M,(H
. n))) and
A79: (
Integral (M,(
lim_inf H)))
<= (
lim_inf IH) by
A76,
Th7;
A80: (
Integral (M,P))
<
+infty by
A4,
MESFUNC5: 96;
now
let n be
Nat;
A81: n
in
NAT by
ORDINAL1:def 12;
(F1
. n)
= (
- (F
. n)) by
A72,
A81;
hence (F1
. n) is
PartFunc of X,
ExtREAL ;
end;
then
reconsider F1 as
Functional_Sequence of X,
ExtREAL by
A72,
SEQFUNC: 1;
A82:
now
let n be
Nat;
n
in
NAT by
ORDINAL1:def 12;
hence (F1
. n)
= (
- (F
. n)) by
A72;
end;
now
let n,m be
Nat;
(F1
. m)
= (
- (F
. m)) by
A82;
then
A83: (
dom (F1
. m))
= (
dom (F
. m)) by
MESFUNC1:def 7;
(F1
. n)
= (
- (F
. n)) by
A82;
then (
dom (F1
. n))
= (
dom (F
. n)) by
MESFUNC1:def 7;
hence (
dom (F1
. n))
= (
dom (F1
. m)) by
A83,
MESFUNC8:def 2;
end;
then
reconsider F1 as
with_the_same_dom
Functional_Sequence of X,
ExtREAL by
MESFUNC8:def 2;
A84: (
Integral (M,(
- (
lim_sup F))))
= (
Integral (M,((
- 1)
(#) (
lim_sup F)))) by
MESFUNC2: 9;
A85:
now
let n be
Nat;
(H
. n)
= (P
- (F
. n)) by
A60;
then (H
. n)
= (P
+ (
- (F
. n))) by
MESFUNC2: 8;
hence (H
. n)
= (P
+ (F1
. n)) by
A82;
end;
(F1
.
0 )
= (
- (F
.
0 )) by
A82;
then
A86: (
dom (F1
.
0 ))
= (
dom (F
.
0 )) by
MESFUNC1:def 7;
then (
dom (F1
.
0 ))
= (
dom (H
.
0 )) by
A1,
A73;
then (
lim_inf H)
= (P
+ (
lim_inf F1)) by
A29,
A26,
A85,
Th11;
then (
lim_inf H)
= (P
+ (
- (
lim_sup F))) by
A82,
A86,
Th15;
then
A87: (
lim_inf H)
= (P
- (
lim_sup F)) by
MESFUNC2: 8;
E
= (
dom (
lim_sup F)) by
A1,
MESFUNC8:def 8;
then E
= (
dom (
- (
lim_sup F))) by
MESFUNC1:def 7;
then
A88: ((
- (
lim_sup F))
| E)
= (
- (
lim_sup F)) by
RELAT_1: 68;
deffunc
I1(
Nat) = (
- (I
. $1));
consider I1 be
sequence of
ExtREAL such that
A89: for n be
Element of
NAT holds (I1
. n)
=
I1(n) from
FUNCT_2:sch 4;
reconsider I1 as
ExtREAL_sequence;
A90:
now
let n be
Nat;
n
in
NAT by
ORDINAL1:def 12;
hence (I1
. n)
= (
- (I
. n)) by
A89;
end;
then
A91: (
- (
lim_inf I1))
= (
lim_sup I) by
Th14;
now
let n be
Nat;
A92: (F
. n)
is_integrable_on M by
A35;
(
Integral (M,(
- (F
. n))))
= (
Integral (M,((
- 1)
(#) (F
. n)))) by
MESFUNC2: 9;
then
A93: (
Integral (M,(
- (F
. n))))
= ((
- jj)
* (
Integral (M,(F
. n)))) by
A92,
MESFUNC5: 110;
A94: (
dom (F
. n))
= E by
A1,
MESFUNC8:def 2;
then E
= (
dom (
- (F
. n))) by
MESFUNC1:def 7;
then
A95: ((
- (F
. n))
| E)
= (
- (F
. n)) by
RELAT_1: 68;
(H
. n)
= (P
- (F
. n)) by
A60;
then
A96: ex E5 be
Element of S st E5
= ((
dom P)
/\ (
dom (F
. n))) & (
Integral (M,(H
. n)))
= ((
Integral (M,(P
| E5)))
+ (
Integral (M,((
- (F
. n))
| E5)))) by
A4,
A92,
Th13;
reconsider In = (I
. n) as
Element of
REAL by
A49;
A97: ((
- 1)
* (I
. n))
= ((
- 1)
* In) by
EXTREAL1: 1;
A98: (
- (I
. n))
= (
- In) by
SUPINF_2: 2;
(P
| E)
= P by
A2,
RELAT_1: 68;
then (
Integral (M,(H
. n)))
= ((
Integral (M,P))
+ (
- (I
. n))) by
A2,
A49,
A96,
A94,
A95,
A93,
A97,
A98;
then (IH
. n)
= ((
Integral (M,P))
+ (
- (I
. n))) by
A78;
hence (IH
. n)
= ((
Integral (M,P))
+ (I1
. n)) by
A90;
end;
then (
lim_inf IH)
= ((
Integral (M,P))
+ (
lim_inf I1)) by
A24,
Th10;
then ((
Integral (M,P))
+ ((
- jj)
* (
Integral (M,(
lim_sup F)))))
<= ((
Integral (M,P))
+ (
- (
lim_sup I))) by
A2,
A61,
A79,
A91,
A87,
A67,
A68,
A71,
A88,
A84,
MESFUNC5: 110;
then ((
- 1)
* (
Integral (M,(
lim_sup F))))
<= (((
- (
lim_sup I))
+ (
Integral (M,P)))
- (
Integral (M,P))) by
A75,
A80,
XXREAL_3: 56;
then ((
- 1)
* (
Integral (M,(
lim_sup F))))
<= ((
- (
lim_sup I))
+ ((
Integral (M,P))
- (
Integral (M,P)))) by
A75,
A80,
XXREAL_3: 30;
then
A99: ((
- 1)
* (
Integral (M,(
lim_sup F))))
<= ((
- (
lim_sup I))
+
0. ) by
XXREAL_3: 7;
((
- 1)
* E1)
= ((
- 1)
* e1) by
EXTREAL1: 1;
then (
- (
Integral (M,(
lim_sup F))))
<= (
- (
lim_sup I)) by
A99,
A70,
XXREAL_3: 4;
then
A100: (
Integral (M,(
lim_sup F)))
>= (
lim_sup I) by
XXREAL_3: 38;
now
A101: (
lim_inf I)
<= (
lim_sup I) by
RINFSUP2: 39;
A102: (
dom (
lim F))
= (
dom (F
.
0 )) by
MESFUNC8:def 9;
assume
A103: for x be
Element of X st x
in E holds (F
# x) is
convergent;
A104: for x be
Element of X st x
in (
dom (
lim F)) holds ((
lim F)
. x)
= ((
lim_inf F)
. x)
proof
let x be
Element of X;
assume
A105: x
in (
dom (
lim F));
then (F
# x) is
convergent by
A1,
A103,
A102;
hence thesis by
A105,
MESFUNC8: 14;
end;
A106: for x be
Element of X st x
in (
dom (
lim F)) holds ((
lim F)
. x)
= ((
lim_sup F)
. x)
proof
let x be
Element of X;
assume
A107: x
in (
dom (
lim F));
then (F
# x) is
convergent by
A1,
A103,
A102;
hence thesis by
A107,
MESFUNC8: 14;
end;
A108: (
dom (
lim F))
= (
dom (
lim_sup F)) by
A102,
MESFUNC8:def 8;
then
A109: (
lim F)
= (
lim_sup F) by
A106,
PARTFUN1: 5;
A110: (
dom (
lim F))
= (
dom (
lim_inf F)) by
A102,
MESFUNC8:def 7;
then (
Integral (M,(
lim F)))
<= (
lim_inf I) by
A57,
A104,
PARTFUN1: 5;
then (
lim_sup I)
<= (
lim_inf I) by
A100,
A109,
XXREAL_0: 2;
then (
lim_inf I)
= (
lim_sup I) by
A101,
XXREAL_0: 1;
hence
A111: I is
convergent by
RINFSUP2: 40;
then (
lim I)
= (
lim_sup I) by
RINFSUP2: 41;
then
A112: (
lim I)
<= (
Integral (M,(
lim F))) by
A100,
A108,
A106,
PARTFUN1: 5;
(
lim I)
= (
lim_inf I) by
A111,
RINFSUP2: 41;
then (
Integral (M,(
lim F)))
<= (
lim I) by
A57,
A110,
A104,
PARTFUN1: 5;
hence (
lim I)
= (
Integral (M,(
lim F))) by
A112,
XXREAL_0: 1;
end;
hence thesis by
A49,
A57,
A100;
end;
theorem ::
MESFUN10:17
Th17: E
= (
dom (F
.
0 )) & E
= (
dom P) & (for n be
Nat holds (F
. n) is E
-measurable) & P
is_integrable_on M & P is
nonnegative & (for x be
Element of X, n be
Nat st x
in E holds (
|.(F
. n).|
. x)
<= (P
. x)) implies ex I be
ExtREAL_sequence st (for n be
Nat holds (I
. n)
= (
Integral (M,(F
. n)))) & (
lim_inf I)
>= (
Integral (M,(
lim_inf F))) & (
lim_sup I)
<= (
Integral (M,(
lim_sup F))) & ((for x be
Element of X st x
in E holds (F
# x) is
convergent) implies I is
convergent & (
lim I)
= (
Integral (M,(
lim F))))
proof
assume that
A1: E
= (
dom (F
.
0 )) and
A2: E
= (
dom P) and
A3: for n be
Nat holds (F
. n) is E
-measurable and
A4: P
is_integrable_on M and
A5: P is
nonnegative and
A6: for x be
Element of X, n be
Nat st x
in E holds (
|.(F
. n).|
. x)
<= (P
. x);
for x be
object st x
in (
eq_dom (P,
+infty )) holds x
in E by
A2,
MESFUNC1:def 15;
then (
eq_dom (P,
+infty ))
c= E by
TARSKI:def 3;
then
A7: (
eq_dom (P,
+infty ))
= (E
/\ (
eq_dom (P,
+infty ))) by
XBOOLE_1: 28;
ex A be
Element of S st A
= (
dom P) & P is A
-measurable by
A4;
then
reconsider E0 = (
eq_dom (P,
+infty )) as
Element of S by
A2,
A7,
MESFUNC1: 33;
reconsider E1 = (E
\ E0) as
Element of S;
deffunc
F1(
Nat) = ((F
. $1)
| E1);
consider F1 be
Functional_Sequence of X,
ExtREAL such that
A8: for n be
Nat holds (F1
. n)
=
F1(n) from
SEQFUNC:sch 1;
A9:
now
let n be
Nat;
(
dom (F
. n))
= E by
A1,
MESFUNC8:def 2;
then (
dom ((F
. n)
| E1))
= E1 by
RELAT_1: 62,
XBOOLE_1: 36;
hence (
dom (F1
. n))
= E1 by
A8;
end;
then
A10: E1
= (
dom (F1
.
0 ));
now
let n,m be
Nat;
thus (
dom (F1
. n))
= E1 by
A9
.= (
dom (F1
. m)) by
A9;
end;
then
reconsider F1 as
with_the_same_dom
Functional_Sequence of X,
ExtREAL by
MESFUNC8:def 2;
set P1 = (P
| E1);
A11: P1 is
nonnegative by
A5,
MESFUNC5: 15;
A12: E1
c= E by
XBOOLE_1: 36;
A13:
now
let x be
Element of X, n be
Nat;
assume
A14: x
in E1;
then
A15: (P1
. x)
= (P
. x) by
FUNCT_1: 49;
x
in E by
A12,
A14;
then x
in (
dom (F
. n)) by
A1,
MESFUNC8:def 2;
then x
in (
dom
|.(F
. n).|) by
MESFUNC1:def 10;
then
A16: (
|.(F
. n).|
. x)
=
|.((F
. n)
. x).| by
MESFUNC1:def 10;
E1
= (
dom (F1
. n)) by
A9;
then
A17: E1
= (
dom
|.(F1
. n).|) by
MESFUNC1:def 10;
(F1
. n)
= ((F
. n)
| E1) by
A8;
then ((F1
. n)
. x)
= ((F
. n)
. x) by
A14,
FUNCT_1: 49;
then (
|.(F
. n).|
. x)
= (
|.(F1
. n).|
. x) by
A14,
A16,
A17,
MESFUNC1:def 10;
hence (
|.(F1
. n).|
. x)
<= (P1
. x) by
A6,
A12,
A14,
A15;
end;
A18: (
dom (
lim F))
= (
dom (F
.
0 )) by
MESFUNC8:def 9;
then
A19: (
dom (
lim F))
= (
dom (
lim_inf F)) by
MESFUNC8:def 7;
A20: (
dom (
lim_inf F))
= E by
A1,
MESFUNC8:def 7;
A21:
now
let x be
Element of X;
assume
A22: x
in (
dom (
lim_inf F1));
then
A23: x
in E1 by
A10,
MESFUNC8:def 7;
now
let n be
Element of
NAT ;
(((F
. n)
| E1)
. x)
= ((F
. n)
. x) by
A23,
FUNCT_1: 49;
then ((F1
. n)
. x)
= ((F
. n)
. x) by
A8;
then ((F1
# x)
. n)
= ((F
. n)
. x) by
MESFUNC5:def 13;
hence ((F1
# x)
. n)
= ((F
# x)
. n) by
MESFUNC5:def 13;
end;
then
A24: (F1
# x)
= (F
# x) by
FUNCT_2: 63;
E1
= (
dom (
lim_inf F1)) by
A10,
MESFUNC8:def 7;
then (
lim_inf (F
# x))
= ((
lim_inf F)
. x) by
A12,
A20,
A22,
MESFUNC8:def 7;
then ((
lim_inf F1)
. x)
= ((
lim_inf F)
. x) by
A22,
A24,
MESFUNC8:def 7;
hence (((
lim_inf F)
| (E
\ E0))
. x)
= ((
lim_inf F1)
. x) by
A23,
FUNCT_1: 49;
end;
E1
= (
dom ((
lim_inf F)
| (E
\ E0))) by
A20,
RELAT_1: 62,
XBOOLE_1: 36;
then (
dom ((
lim_inf F)
| (E
\ E0)))
= (
dom (
lim_inf F1)) by
A10,
MESFUNC8:def 7;
then
A25: ((
lim_inf F)
| (E
\ E0))
= (
lim_inf F1) by
A21,
PARTFUN1: 5;
A26: (
dom (
lim_sup F))
= E by
A1,
MESFUNC8:def 8;
A27:
now
let x be
Element of X;
assume
A28: x
in (
dom (
lim_sup F1));
then
A29: x
in E1 by
A10,
MESFUNC8:def 8;
now
let n be
Element of
NAT ;
(((F
. n)
| E1)
. x)
= ((F
. n)
. x) by
A29,
FUNCT_1: 49;
then ((F1
. n)
. x)
= ((F
. n)
. x) by
A8;
then ((F1
# x)
. n)
= ((F
. n)
. x) by
MESFUNC5:def 13;
hence ((F1
# x)
. n)
= ((F
# x)
. n) by
MESFUNC5:def 13;
end;
then
A30: (F1
# x)
= (F
# x) by
FUNCT_2: 63;
E1
= (
dom (
lim_sup F1)) by
A10,
MESFUNC8:def 8;
then (
lim_sup (F
# x))
= ((
lim_sup F)
. x) by
A12,
A26,
A28,
MESFUNC8:def 8;
then ((
lim_sup F1)
. x)
= ((
lim_sup F)
. x) by
A28,
A30,
MESFUNC8:def 8;
hence (((
lim_sup F)
| (E
\ E0))
. x)
= ((
lim_sup F1)
. x) by
A29,
FUNCT_1: 49;
end;
E1
= (
dom ((
lim_sup F)
| (E
\ E0))) by
A26,
RELAT_1: 62,
XBOOLE_1: 36;
then (
dom ((
lim_sup F)
| (E
\ E0)))
= (
dom (
lim_sup F1)) by
A10,
MESFUNC8:def 8;
then
A31: ((
lim_sup F)
| (E
\ E0))
= (
lim_sup F1) by
A27,
PARTFUN1: 5;
A32: (
dom (P
| E1))
= E1 by
A2,
RELAT_1: 62,
XBOOLE_1: 36;
A33:
now
assume (
eq_dom (P1,
+infty ))
<>
{} ;
then
consider x be
object such that
A34: x
in (
eq_dom (P1,
+infty )) by
XBOOLE_0:def 1;
reconsider x as
Element of X by
A34;
(P1
. x)
=
+infty by
A34,
MESFUNC1:def 15;
then
consider y be
R_eal such that
A35: y
= (P1
. x) and
A36:
+infty
= y;
A37: x
in E1 by
A32,
A34,
MESFUNC1:def 15;
then y
= (P
. x) by
A35,
FUNCT_1: 49;
then x
in (
eq_dom (P,
+infty )) by
A2,
A12,
A36,
A37,
MESFUNC1:def 15;
hence contradiction by
A37,
XBOOLE_0:def 5;
end;
A38: for n be
Nat holds (F1
. n) is E1
-measurable
proof
let n be
Nat;
(
dom (F
. n))
= E by
A1,
MESFUNC8:def 2;
then
A39: E1
= ((
dom (F
. n))
/\ E1) by
XBOOLE_1: 28,
XBOOLE_1: 36;
(F
. n) is E
-measurable by
A3;
then (F
. n) is E1
-measurable by
MESFUNC1: 30,
XBOOLE_1: 36;
then ((F
. n)
| E1) is E1
-measurable by
A39,
MESFUNC5: 42;
hence thesis by
A8;
end;
P1
is_integrable_on M by
A4,
MESFUNC5: 112;
then
consider I be
ExtREAL_sequence such that
A40: for n be
Nat holds (I
. n)
= (
Integral (M,(F1
. n))) and
A41: (
lim_inf I)
>= (
Integral (M,(
lim_inf F1))) and
A42: (
lim_sup I)
<= (
Integral (M,(
lim_sup F1))) and (for x be
Element of X st x
in E1 holds (F1
# x) is
convergent) implies I is
convergent & (
lim I)
= (
Integral (M,(
lim F1))) by
A32,
A10,
A11,
A13,
A38,
A33,
Lm1;
(P
"
{
+infty })
= E0 by
MESFUNC5: 30;
then
A43: (M
. E0)
=
0 by
A4,
MESFUNC5: 105;
A44: for n be
Nat holds (I
. n)
= (
Integral (M,(F
. n)))
proof
let n be
Nat;
A45: E
= (
dom (F
. n)) by
A1,
MESFUNC8:def 2;
A46: (F
. n) is E
-measurable by
A3;
|.(F
. n).|
is_integrable_on M by
A1,
A2,
A3,
A4,
A6,
Th16;
then (F
. n)
is_integrable_on M by
A45,
A46,
MESFUNC5: 100;
then (
Integral (M,(F
. n)))
= ((
Integral (M,((F
. n)
| E0)))
+ (
Integral (M,((F
. n)
| E1)))) by
A45,
MESFUNC5: 99;
then
A47: (
Integral (M,(F
. n)))
= (
0.
+ (
Integral (M,((F
. n)
| E1)))) by
A3,
A43,
A45,
MESFUNC5: 94;
(I
. n)
= (
Integral (M,(F1
. n))) by
A40;
then (I
. n)
= (
Integral (M,((F
. n)
| E1))) by
A8;
hence thesis by
A47,
XXREAL_3: 4;
end;
(
lim_inf F) is E
-measurable by
A1,
A3,
MESFUNC8: 24;
then
A48: (
Integral (M,((
lim_inf F)
| (E
\ E0))))
= (
Integral (M,(
lim_inf F))) by
A43,
A20,
MESFUNC5: 95;
(
lim_sup F) is E
-measurable by
A1,
A3,
MESFUNC8: 23;
then
A49: (
Integral (M,((
lim_sup F)
| (E
\ E0))))
= (
Integral (M,(
lim_sup F))) by
A43,
A26,
MESFUNC5: 95;
A50: (
dom (
lim F))
= (
dom (
lim_sup F)) by
A18,
MESFUNC8:def 8;
now
assume
A51: for x be
Element of X st x
in E holds (F
# x) is
convergent;
A52: for x be
Element of X st x
in (
dom (
lim F)) holds ((
lim F)
. x)
= ((
lim_inf F)
. x)
proof
let x be
Element of X;
assume
A53: x
in (
dom (
lim F));
then (F
# x) is
convergent by
A1,
A18,
A51;
hence thesis by
A53,
MESFUNC8: 14;
end;
then
A54: (
lim F)
= (
lim_inf F) by
A19,
PARTFUN1: 5;
A55: (
lim_inf I)
<= (
lim_sup I) by
RINFSUP2: 39;
A56: for x be
Element of X st x
in (
dom (
lim F)) holds ((
lim F)
. x)
= ((
lim_sup F)
. x)
proof
let x be
Element of X;
assume
A57: x
in (
dom (
lim F));
then (F
# x) is
convergent by
A1,
A18,
A51;
hence thesis by
A57,
MESFUNC8: 14;
end;
then (
lim F)
= (
lim_sup F) by
A50,
PARTFUN1: 5;
then (
lim_sup I)
<= (
lim_inf I) by
A41,
A42,
A25,
A31,
A54,
XXREAL_0: 2;
then (
lim_inf I)
= (
lim_sup I) by
A55,
XXREAL_0: 1;
hence
A58: I is
convergent by
RINFSUP2: 40;
then (
lim I)
= (
lim_sup I) by
RINFSUP2: 41;
then
A59: (
lim I)
<= (
Integral (M,(
lim F))) by
A42,
A49,
A31,
A50,
A56,
PARTFUN1: 5;
(
lim I)
= (
lim_inf I) by
A58,
RINFSUP2: 41;
then (
Integral (M,(
lim F)))
<= (
lim I) by
A41,
A48,
A25,
A19,
A52,
PARTFUN1: 5;
hence (
lim I)
= (
Integral (M,(
lim F))) by
A59,
XXREAL_0: 1;
end;
hence thesis by
A41,
A42,
A44,
A48,
A49,
A25,
A31;
end;
theorem ::
MESFUN10:18
E
= (
dom (F
.
0 )) & (for n holds (F
. n) is
nonnegative & (F
. n) is E
-measurable) & (for x, n, m st x
in E & n
<= m holds ((F
. n)
. x)
>= ((F
. m)
. x)) & (
Integral (M,((F
.
0 )
| E)))
<
+infty implies ex I be
ExtREAL_sequence st (for n be
Nat holds (I
. n)
= (
Integral (M,(F
. n)))) & I is
convergent & (
lim I)
= (
Integral (M,(
lim F)))
proof
assume that
A1: E
= (
dom (F
.
0 )) and
A2: for n holds (F
. n) is
nonnegative & (F
. n) is E
-measurable and
A3: for x, n, m st x
in E & n
<= m holds ((F
. n)
. x)
>= ((F
. m)
. x) and
A4: (
Integral (M,((F
.
0 )
| E)))
<
+infty ;
A5: (F
.
0 ) is
nonnegative by
A2;
A6: (
dom (F
.
0 ))
= (
dom
|.(F
.
0 ).|) by
MESFUNC1:def 10;
A7: for x be
Element of X st x
in (
dom (F
.
0 )) holds ((F
.
0 )
. x)
= (
|.(F
.
0 ).|
. x)
proof
let x be
Element of X;
0
<= ((F
.
0 )
. x) by
A5,
SUPINF_2: 51;
then
A8:
|.((F
.
0 )
. x).|
= ((F
.
0 )
. x) by
EXTREAL1:def 1;
assume x
in (
dom (F
.
0 ));
hence thesis by
A6,
A8,
MESFUNC1:def 10;
end;
A9: (F
.
0 ) is E
-measurable by
A2;
then (
Integral (M,(F
.
0 )))
= (
integral+ (M,(F
.
0 ))) by
A1,
A5,
MESFUNC5: 88;
then (
integral+ (M,(F
.
0 )))
<
+infty by
A1,
A4,
RELAT_1: 68;
then
A10: (
integral+ (M,
|.(F
.
0 ).|))
<
+infty by
A6,
A7,
PARTFUN1: 5;
A11: (
max+ (F
.
0 )) is E
-measurable by
A2,
MESFUNC2: 25;
for x be
object st x
in (
dom (
max- (F
.
0 ))) holds
0.
<= ((
max- (F
.
0 ))
. x) by
MESFUNC2: 13;
then
A12: (
max- (F
.
0 )) is
nonnegative by
SUPINF_2: 52;
A13: for x be
Element of X, n be
Nat st x
in E holds (
|.(F
. n).|
. x)
<= ((F
.
0 )
. x)
proof
let x be
Element of X, n be
Nat;
assume
A14: x
in E;
(F
. n) is
nonnegative by
A2;
then
0
<= ((F
. n)
. x) by
SUPINF_2: 51;
then
|.((F
. n)
. x).|
= ((F
. n)
. x) by
EXTREAL1:def 1;
then
A15:
|.((F
. n)
. x).|
<= ((F
.
0 )
. x) by
A3,
A14;
(
dom (F
. n))
= (
dom
|.(F
. n).|) by
MESFUNC1:def 10;
then x
in (
dom
|.(F
. n).|) by
A1,
A14,
MESFUNC8:def 2;
hence thesis by
A15,
MESFUNC1:def 10;
end;
A16: for x be
Element of X st x
in E holds (F
# x) is
convergent
proof
let x be
Element of X;
assume
A17: x
in E;
now
let n,m be
Nat;
assume m
<= n;
then ((F
. n)
. x)
<= ((F
. m)
. x) by
A3,
A17;
then ((F
# x)
. n)
<= ((F
. m)
. x) by
MESFUNC5:def 13;
hence ((F
# x)
. n)
<= ((F
# x)
. m) by
MESFUNC5:def 13;
end;
then (F
# x) is
non-increasing by
RINFSUP2: 7;
hence thesis by
RINFSUP2: 36;
end;
A18: (
dom (
max+ (F
.
0 )))
= (
dom (F
.
0 )) by
MESFUNC2:def 2;
then
A19: ((
max+ (F
.
0 ))
| E)
= (
max+ (F
.
0 )) by
A1,
RELAT_1: 68;
for x be
object st x
in (
dom (
max+ (F
.
0 ))) holds
0.
<= ((
max+ (F
.
0 ))
. x) by
MESFUNC2: 12;
then
A20: (
max+ (F
.
0 )) is
nonnegative by
SUPINF_2: 52;
then
A21: (
dom ((
max+ (F
.
0 ))
+ (
max- (F
.
0 ))))
= ((
dom (
max+ (F
.
0 )))
/\ (
dom (
max- (F
.
0 )))) by
A12,
MESFUNC5: 22;
A22: (
dom (
max- (F
.
0 )))
= (
dom (F
.
0 )) by
MESFUNC2:def 3;
then
A23: ((
max- (F
.
0 ))
| E)
= (
max- (F
.
0 )) by
A1,
RELAT_1: 68;
(
max- (F
.
0 )) is E
-measurable by
A1,
A2,
MESFUNC2: 26;
then ex C be
Element of S st C
= (
dom ((
max+ (F
.
0 ))
+ (
max- (F
.
0 )))) & (
integral+ (M,((
max+ (F
.
0 ))
+ (
max- (F
.
0 )))))
= ((
integral+ (M,((
max+ (F
.
0 ))
| C)))
+ (
integral+ (M,((
max- (F
.
0 ))
| C)))) by
A1,
A18,
A22,
A20,
A12,
A11,
MESFUNC5: 78;
then
A24: ((
integral+ (M,(
max+ (F
.
0 ))))
+ (
integral+ (M,(
max- (F
.
0 )))))
<
+infty by
A1,
A18,
A22,
A21,
A19,
A23,
A10,
MESFUNC2: 24;
0
<= (
integral+ (M,(
max- (F
.
0 )))) by
A1,
A9,
A22,
A12,
MESFUNC2: 26,
MESFUNC5: 79;
then (
integral+ (M,(
max+ (F
.
0 ))))
<>
+infty by
A24,
XXREAL_3:def 2;
then
A25: (
integral+ (M,(
max+ (F
.
0 ))))
<
+infty by
XXREAL_0: 4;
0
<= (
integral+ (M,(
max+ (F
.
0 )))) by
A1,
A9,
A18,
A20,
MESFUNC2: 25,
MESFUNC5: 79;
then (
integral+ (M,(
max- (F
.
0 ))))
<>
+infty by
A24,
XXREAL_3:def 2;
then (
integral+ (M,(
max- (F
.
0 ))))
<
+infty by
XXREAL_0: 4;
then (F
.
0 )
is_integrable_on M by
A1,
A9,
A25;
then ex I be
ExtREAL_sequence st (for n be
Nat holds (I
. n)
= (
Integral (M,(F
. n)))) & (
lim_inf I)
>= (
Integral (M,(
lim_inf F))) & (
lim_sup I)
<= (
Integral (M,(
lim_sup F))) & ((for x be
Element of X st x
in E holds (F
# x) is
convergent) implies I is
convergent & (
lim I)
= (
Integral (M,(
lim F)))) by
A1,
A2,
A13,
Th17;
hence thesis by
A16;
end;
definition
let X be
set, F be
Functional_Sequence of X,
ExtREAL ;
::
MESFUN10:def1
attr F is
uniformly_bounded means ex K be
Real st for n be
Nat, x be
set st x
in (
dom (F
.
0 )) holds
|.((F
. n)
. x).|
<= K;
end
::$Notion-Name
theorem ::
MESFUN10:19
(M
. E)
<
+infty & E
= (
dom (F
.
0 )) & (for n be
Nat holds (F
. n) is E
-measurable) & F is
uniformly_bounded & (for x be
Element of X st x
in E holds (F
# x) is
convergent) implies (for n be
Nat holds (F
. n)
is_integrable_on M) & (
lim F)
is_integrable_on M & ex I be
ExtREAL_sequence st (for n be
Nat holds (I
. n)
= (
Integral (M,(F
. n)))) & I is
convergent & (
lim I)
= (
Integral (M,(
lim F)))
proof
assume that
A1: (M
. E)
<
+infty and
A2: E
= (
dom (F
.
0 )) and
A3: for n be
Nat holds (F
. n) is E
-measurable and
A4: F is
uniformly_bounded and
A5: for x be
Element of X st x
in E holds (F
# x) is
convergent;
consider K1 be
Real such that
A6: for n be
Nat, x be
set st x
in (
dom (F
.
0 )) holds
|.((F
. n)
. x).|
<= K1 by
A4;
set K = (
max (K1,1));
K
in
REAL by
XREAL_0:def 1;
then
consider h be
PartFunc of X,
ExtREAL such that
A7: h
is_simple_func_in S and
A8: (
dom h)
= E and
A9: for x be
object st x
in E holds (h
. x)
= K by
MESFUNC5: 41,
NUMBERS: 31;
A10: (
dom h)
= (
dom
|.h.|) by
MESFUNC1:def 10;
A11: K
>
0 by
XXREAL_0: 30;
then
A12: (K
*
+infty )
=
+infty by
XXREAL_3:def 5;
for x be
object st x
in E holds (h
. x)
>=
0. by
A11,
A9;
then
A13: h is
nonnegative by
A8,
SUPINF_2: 52;
then
A14: (
Integral (M,h))
= (
integral' (M,h)) by
A7,
MESFUNC5: 89;
A15: (
integral' (M,h))
= (K
* (M
. (
dom h))) by
A11,
A8,
A9,
MESFUNC5: 104;
A16: for x be
Element of X st x
in (
dom h) holds (h
. x)
= (
|.h.|
. x)
proof
let x be
Element of X;
assume x
in (
dom h);
then
A17: x
in (
dom
|.h.|) by
MESFUNC1:def 10;
0
<= (h
. x) by
A13,
SUPINF_2: 51;
then
|.(h
. x).|
= (h
. x) by
EXTREAL1:def 1;
hence thesis by
A17,
MESFUNC1:def 10;
end;
(
Integral (M,h))
= (
integral+ (M,h)) by
A7,
A13,
MESFUNC5: 89;
then (
integral+ (M,h))
<
+infty by
A1,
A11,
A8,
A15,
A12,
A14,
XXREAL_3: 72;
then
A18: (
integral+ (M,
|.h.|))
<
+infty by
A10,
A16,
PARTFUN1: 5;
A19: (
dom (
max+ h))
= (
dom h) by
MESFUNC2:def 2;
then
A20: ((
max+ h)
| E)
= (
max+ h) by
A8,
RELAT_1: 68;
A21: (
max+ h) is E
-measurable by
A7,
MESFUNC2: 25,
MESFUNC2: 34;
for x be
object st x
in (
dom (
max- h)) holds
0.
<= ((
max- h)
. x) by
MESFUNC2: 13;
then
A22: (
max- h) is
nonnegative by
SUPINF_2: 52;
A23: K
>= K1 by
XXREAL_0: 25;
A24: for n be
Nat, x be
set st x
in (
dom (F
.
0 )) holds
|.((F
. n)
. x).|
<= K
proof
let n be
Nat, x be
set;
assume x
in (
dom (F
.
0 ));
then
|.((F
. n)
. x).|
<= K1 by
A6;
hence thesis by
A23,
XXREAL_0: 2;
end;
A25: for x be
Element of X, n be
Nat st x
in E holds (
|.(F
. n).|
. x)
<= (h
. x)
proof
let x be
Element of X, n be
Nat;
assume
A26: x
in E;
(
dom (F
. n))
= (
dom
|.(F
. n).|) by
MESFUNC1:def 10;
then x
in (
dom
|.(F
. n).|) by
A2,
A26,
MESFUNC8:def 2;
then
A27: (
|.(F
. n).|
. x)
=
|.((F
. n)
. x).| by
MESFUNC1:def 10;
|.((F
. n)
. x).|
<= K by
A2,
A24,
A26;
hence thesis by
A9,
A26,
A27;
end;
for x be
object st x
in (
dom (
max+ h)) holds
0.
<= ((
max+ h)
. x) by
MESFUNC2: 12;
then
A28: (
max+ h) is
nonnegative by
SUPINF_2: 52;
then
A29: (
dom ((
max+ h)
+ (
max- h)))
= ((
dom (
max+ h))
/\ (
dom (
max- h))) by
A22,
MESFUNC5: 22;
A30: (
dom (
max- h))
= (
dom h) by
MESFUNC2:def 3;
then
A31: ((
max- h)
| E)
= (
max- h) by
A8,
RELAT_1: 68;
(
max- h) is E
-measurable by
A7,
A8,
MESFUNC2: 26,
MESFUNC2: 34;
then ex C be
Element of S st C
= (
dom ((
max+ h)
+ (
max- h))) & (
integral+ (M,((
max+ h)
+ (
max- h))))
= ((
integral+ (M,((
max+ h)
| C)))
+ (
integral+ (M,((
max- h)
| C)))) by
A8,
A19,
A30,
A21,
A28,
A22,
MESFUNC5: 78;
then
A32: ((
integral+ (M,(
max+ h)))
+ (
integral+ (M,(
max- h))))
<
+infty by
A8,
A19,
A30,
A29,
A20,
A31,
A18,
MESFUNC2: 24;
A33: for x be
Element of X st x
in (
dom (
lim F)) holds ((
lim F)
. x)
= ((
lim_inf F)
. x)
proof
let x be
Element of X;
assume
A34: x
in (
dom (
lim F));
then x
in E by
A2,
MESFUNC8:def 9;
then (F
# x) is
convergent by
A5;
hence thesis by
A34,
MESFUNC8: 14;
end;
A35: (
dom (
lim_inf F))
= (
dom (F
.
0 )) by
MESFUNC8:def 7;
A36: h is E
-measurable by
A7,
MESFUNC2: 34;
then
0
<= (
integral+ (M,(
max- h))) by
A8,
A30,
A22,
MESFUNC2: 26,
MESFUNC5: 79;
then (
integral+ (M,(
max+ h)))
<>
+infty by
A32,
XXREAL_3:def 2;
then
A37: (
integral+ (M,(
max+ h)))
<
+infty by
XXREAL_0: 4;
0
<= (
integral+ (M,(
max+ h))) by
A8,
A36,
A19,
A28,
MESFUNC2: 25,
MESFUNC5: 79;
then (
integral+ (M,(
max- h)))
<>
+infty by
A32,
XXREAL_3:def 2;
then (
integral+ (M,(
max- h)))
<
+infty by
XXREAL_0: 4;
then
A38: h
is_integrable_on M by
A8,
A36,
A37;
then
A39: ex I be
ExtREAL_sequence st (for n be
Nat holds (I
. n)
= (
Integral (M,(F
. n)))) & (
lim_inf I)
>= (
Integral (M,(
lim_inf F))) & (
lim_sup I)
<= (
Integral (M,(
lim_sup F))) & ((for x be
Element of X st x
in E holds (F
# x) is
convergent) implies I is
convergent & (
lim I)
= (
Integral (M,(
lim F)))) by
A2,
A3,
A8,
A13,
A25,
Th17;
A40:
now
let n be
Nat;
A41: E
= (
dom (F
. n)) by
A2,
MESFUNC8:def 2;
A42: (F
. n) is E
-measurable by
A3;
|.(F
. n).|
is_integrable_on M by
A2,
A3,
A8,
A38,
A25,
Th16;
hence (F
. n)
is_integrable_on M by
A41,
A42,
MESFUNC5: 100;
end;
A43:
|.(
lim_inf F).|
is_integrable_on M by
A2,
A3,
A8,
A38,
A25,
Th16;
(
dom (
lim F))
= (
dom (F
.
0 )) by
MESFUNC8:def 9;
then
A44: (
lim F)
= (
lim_inf F) by
A35,
A33,
PARTFUN1: 5;
then (
lim F) is E
-measurable by
A2,
A3,
MESFUNC8: 24;
hence thesis by
A2,
A5,
A43,
A40,
A35,
A44,
A39,
MESFUNC5: 100;
end;
definition
let X be
set, F be
Functional_Sequence of X,
ExtREAL , f be
PartFunc of X,
ExtREAL ;
::
MESFUN10:def2
pred F
is_uniformly_convergent_to f means F is
with_the_same_dom & (
dom (F
.
0 ))
= (
dom f) & for e be
Real st e
>
0 holds ex N be
Nat st for n be
Nat, x be
set st n
>= N & x
in (
dom (F
.
0 )) holds
|.(((F
. n)
. x)
- (f
. x)).|
< e;
end
theorem ::
MESFUN10:20
Th20: F1
is_uniformly_convergent_to f implies for x be
Element of X st x
in (
dom (F1
.
0 )) holds (F1
# x) is
convergent & (
lim (F1
# x))
= (f
. x)
proof
assume
A1: F1
is_uniformly_convergent_to f;
let x be
Element of X;
assume
A2: x
in (
dom (F1
.
0 ));
per cases by
XXREAL_0: 14;
suppose (f
. x)
in
REAL ;
then
reconsider g = (f
. x) as
Real;
A3:
now
let e be
Real;
assume
0
< e;
then
consider N be
Nat such that
A4: for n be
Nat, x be
set st n
>= N & x
in (
dom (F1
.
0 )) holds
|.(((F1
. n)
. x)
- (f
. x)).|
< e by
A1;
take N;
hereby
let m be
Nat;
assume N
<= m;
then
|.(((F1
. m)
. x)
- (f
. x)).|
< e by
A2,
A4;
hence
|.(((F1
# x)
. m)
- g).|
< e by
MESFUNC5:def 13;
end;
end;
then
A5: (F1
# x) is
convergent_to_finite_number;
then (F1
# x) is
convergent;
hence thesis by
A3,
A5,
MESFUNC5:def 12;
end;
suppose
A6: (f
. x)
=
+infty ;
now
let e be
Real;
assume
0
< e;
then
consider N be
Nat such that
A7: for n be
Nat, x be
set st n
>= N & x
in (
dom (F1
.
0 )) holds
|.(((F1
. n)
. x)
- (f
. x)).|
< e by
A1;
take N;
hereby
let n be
Nat;
assume n
>= N;
then
|.(((F1
. n)
. x)
- (f
. x)).|
< e by
A2,
A7;
then
A8:
|.(
- (((F1
. n)
. x)
- (f
. x))).|
< e by
EXTREAL1: 29;
((F1
. n)
. x)
= ((F1
# x)
. n) by
MESFUNC5:def 13;
then (
- (((F1
# x)
. n)
- (f
. x)))
< e by
A8,
EXTREAL1: 21;
then ((f
. x)
- ((F1
# x)
. n))
< e by
XXREAL_3: 26;
then ((F1
# x)
. n)
=
+infty by
A6,
XXREAL_3: 54;
hence e
<= ((F1
# x)
. n) by
XXREAL_0: 3;
end;
end;
then
A9: (F1
# x) is
convergent_to_+infty;
then (F1
# x) is
convergent;
hence thesis by
A6,
A9,
MESFUNC5:def 12;
end;
suppose
A10: (f
. x)
=
-infty ;
now
let e be
Real;
assume e
<
0 ;
then (
-
0 )
< (
- e) by
XREAL_1: 24;
then
consider N be
Nat such that
A11: for n be
Nat, x be
set st n
>= N & x
in (
dom (F1
.
0 )) holds
|.(((F1
. n)
. x)
- (f
. x)).|
< (
- e) by
A1;
take N;
hereby
let n be
Nat;
assume n
>= N;
then
A12:
|.(((F1
. n)
. x)
- (f
. x)).|
< (
- e) by
A2,
A11;
((F1
. n)
. x)
= ((F1
# x)
. n) by
MESFUNC5:def 13;
then (((F1
# x)
. n)
- (f
. x))
< (
- e) by
A12,
EXTREAL1: 21;
then ((F1
# x)
. n)
=
-infty by
A10,
XXREAL_3: 54;
hence e
>= ((F1
# x)
. n) by
XXREAL_0: 5;
end;
end;
then
A13: (F1
# x) is
convergent_to_-infty;
then (F1
# x) is
convergent;
hence thesis by
A10,
A13,
MESFUNC5:def 12;
end;
end;
theorem ::
MESFUN10:21
(M
. E)
<
+infty & E
= (
dom (F
.
0 )) & (for n be
Nat holds (F
. n)
is_integrable_on M) & F
is_uniformly_convergent_to f implies f
is_integrable_on M & ex I be
ExtREAL_sequence st (for n be
Nat holds (I
. n)
= (
Integral (M,(F
. n)))) & I is
convergent & (
lim I)
= (
Integral (M,f))
proof
assume that
A1: (M
. E)
<
+infty and
A2: E
= (
dom (F
.
0 )) and
A3: for n be
Nat holds (F
. n)
is_integrable_on M and
A4: F
is_uniformly_convergent_to f;
reconsider e = (1
/ 2) as
Real;
consider N be
Nat such that
A5: for n be
Nat, x be
set st n
>= N & x
in (
dom (F
.
0 )) holds
|.(((F
. n)
. x)
- (f
. x)).|
< e by
A4;
reconsider N1 = N as
Nat;
consider h be
PartFunc of X,
ExtREAL such that
A6: h
is_simple_func_in S and
A7: (
dom h)
= E and
A8: for x be
object st x
in E holds (h
. x)
=
1. by
MESFUNC5: 41;
A9: (
max- h) is E
-measurable by
A6,
A7,
MESFUNC2: 26,
MESFUNC2: 34;
for x be
object st x
in E holds (h
. x)
>=
0. by
A8;
then
A10: h is
nonnegative by
A7,
SUPINF_2: 52;
then
A11: (
Integral (M,h))
= (
integral' (M,h)) by
A6,
MESFUNC5: 89;
set AFN =
|.(F
. N).|;
A12: (
dom (F
. N))
= (
dom AFN) by
MESFUNC1:def 10;
now
let x be
object;
assume x
in (
dom AFN);
then (AFN
. x)
=
|.((F
. N)
. x).| by
MESFUNC1:def 10;
hence
0
<= (AFN
. x) by
EXTREAL1: 14;
end;
then
A13: AFN is
nonnegative by
SUPINF_2: 52;
then
A14: (
dom (AFN
+ h))
= ((
dom AFN)
/\ (
dom h)) by
A10,
MESFUNC5: 22;
A15: for x be
set st x
in (
dom (F
.
0 )) holds
|.(((F
. N)
. x)
- (f
. x)).|
< (1
/ 2) by
A5;
A16:
now
let x be
set, n be
Nat;
assume that
A17: n
>= N and
A18: x
in (
dom (F
.
0 ));
A19:
|.(((F
. n)
. x)
- (f
. x)).|
< (jj
/ 2) by
A5,
A17,
A18;
A20:
|.(((F
. N)
. x)
- (f
. x)).|
< (jj
/ 2) by
A5,
A18;
A21:
now
A22:
|.(((F
. n)
. x)
- (f
. x)).|
< 1 by
A19,
XXREAL_0: 2;
then
A23: (((F
. n)
. x)
- (f
. x))
<
1. by
EXTREAL1: 21;
A24:
|.(((F
. N)
. x)
- (f
. x)).|
< 1 by
A20,
XXREAL_0: 2;
then
A25: (
-
1. )
< (((F
. N)
. x)
- (f
. x)) by
EXTREAL1: 21;
A26: (((F
. N)
. x)
- (f
. x))
<
1. by
A24,
EXTREAL1: 21;
assume
A27: (f
. x)
=
+infty or (f
. x)
=
-infty ;
(
-
1. )
< (((F
. n)
. x)
- (f
. x)) by
A22,
EXTREAL1: 21;
then ((F
. n)
. x)
=
+infty & ((F
. N)
. x)
=
+infty or ((F
. n)
. x)
=
-infty & ((F
. N)
. x)
=
-infty by
A27,
A25,
A23,
A26,
XXREAL_3: 53,
XXREAL_3: 54;
hence
|.((F
. n)
. x).|
<= (
|.((F
. N)
. x).|
+
1. ) by
EXTREAL1: 30,
XXREAL_3: 52;
end;
(
dom (AFN
+ h))
= ((
dom AFN)
/\ (
dom h)) by
A10,
A13,
MESFUNC5: 22;
then (
dom (AFN
+ h))
= (E
/\ E) by
A2,
A7,
A12,
MESFUNC8:def 2;
then ((AFN
. x)
+ (h
. x))
= ((AFN
+ h)
. x) by
A2,
A18,
MESFUNC1:def 3;
then
A28: ((AFN
. x)
+
1. )
= ((AFN
+ h)
. x) by
A2,
A8,
A18;
(
dom (F
. n))
= E by
A2,
MESFUNC8:def 2;
then
A29: x
in (
dom
|.(F
. n).|) by
A2,
A18,
MESFUNC1:def 10;
A30:
now
A31:
0
<=
|.(((F
. n)
. x)
- (f
. x)).| by
EXTREAL1: 14;
A32: (jj
/ 2)
in
REAL by
XREAL_0:def 1;
then
|.(((F
. n)
. x)
- (f
. x)).|
<
+infty by
A19,
XXREAL_0: 2,
XXREAL_0: 9;
then
reconsider a =
|.(((F
. n)
. x)
- (f
. x)).| as
Element of
REAL by
A31,
XXREAL_0: 14;
|.((f
. x)
- ((F
. N)
. x)).|
< (jj
/ 2) by
A20,
MESFUNC5: 1;
then
A33:
|.((f
. x)
- ((F
. N)
. x)).|
<
+infty by
XXREAL_0: 2,
XXREAL_0: 9,
A32;
0
<=
|.((f
. x)
- ((F
. N)
. x)).| by
EXTREAL1: 14;
then
reconsider b =
|.((f
. x)
- ((F
. N)
. x)).| as
Element of
REAL by
A33,
XXREAL_0: 14;
assume
A34: (f
. x)
in
REAL ;
A35:
now
assume ((F
. N)
. x)
=
+infty or ((F
. N)
. x)
=
-infty ;
then (((F
. N)
. x)
- (f
. x))
=
+infty or (((F
. N)
. x)
- (f
. x))
=
-infty by
A34,
XXREAL_3: 13,
XXREAL_3: 14;
then jj
<
|.(((F
. N)
. x)
- (f
. x)).| by
EXTREAL1: 30,
XXREAL_0: 9;
hence contradiction by
A15,
A18,
XXREAL_0: 2;
end;
A36:
now
assume ((F
. n)
. x)
=
+infty or ((F
. n)
. x)
=
-infty ;
then (((F
. n)
. x)
- (f
. x))
=
+infty or (((F
. n)
. x)
- (f
. x))
=
-infty by
A34,
XXREAL_3: 13,
XXREAL_3: 14;
hence contradiction by
A19,
EXTREAL1: 30,
XXREAL_0: 9,
A32;
end;
then ((F
. n)
. x)
in
REAL by
XXREAL_0: 14;
then
A37: (
|.((F
. n)
. x).|
-
|.((F
. N)
. x).|)
<=
|.(((F
. n)
. x)
- ((F
. N)
. x)).| by
EXTREAL1: 31;
b
<= (1
/ 2) by
A20,
MESFUNC5: 1;
then (a
+ b)
< ((1
/ 2)
+ (1
/ 2)) by
A19,
XREAL_1: 8;
then
A38: (
|.(((F
. n)
. x)
- (f
. x)).|
+
|.((f
. x)
- ((F
. N)
. x)).|)
< 1 by
SUPINF_2: 1;
((
- (f
. x))
+ (f
. x))
=
0. by
XXREAL_3: 7;
then (((F
. n)
. x)
- ((F
. N)
. x))
= ((((F
. n)
. x)
+ ((
- (f
. x))
+ (f
. x)))
- ((F
. N)
. x)) by
XXREAL_3: 4;
then (((F
. n)
. x)
- ((F
. N)
. x))
= (((((F
. n)
. x)
+ (
- (f
. x)))
+ (f
. x))
- ((F
. N)
. x)) by
A34,
A36,
XXREAL_3: 29;
then (((F
. n)
. x)
- ((F
. N)
. x))
= ((((F
. n)
. x)
- (f
. x))
+ ((f
. x)
- ((F
. N)
. x))) by
A34,
A35,
XXREAL_3: 30;
then
|.(((F
. n)
. x)
- ((F
. N)
. x)).|
<= (
|.(((F
. n)
. x)
- (f
. x)).|
+
|.((f
. x)
- ((F
. N)
. x)).|) by
EXTREAL1: 24;
then
|.(((F
. n)
. x)
- ((F
. N)
. x)).|
< 1 by
A38,
XXREAL_0: 2;
then (
|.((F
. n)
. x).|
-
|.((F
. N)
. x).|)
<=
1. by
A37,
XXREAL_0: 2;
hence
|.((F
. n)
. x).|
<= (
|.((F
. N)
. x).|
+
1. ) by
XXREAL_3: 52;
end;
x
in (
dom AFN) by
A12,
A18,
MESFUNC8:def 2;
then
|.((F
. n)
. x).|
<= ((AFN
. x)
+
1. ) by
A30,
A21,
MESFUNC1:def 10,
XXREAL_0: 14;
hence (
|.(F
. n).|
. x)
<= ((AFN
+ h)
. x) by
A28,
A29,
MESFUNC1:def 10;
end;
A39: for x be
Element of X, n be
Nat st x
in E holds (
|.((F
^\ N1)
. n).|
. x)
<= ((AFN
+ h)
. x)
proof
let x be
Element of X, n be
Nat;
A40: ((F
^\ N1)
. n)
= (F
. (n
+ N)) by
NAT_1:def 3;
assume x
in E;
hence thesis by
A2,
A16,
A40,
NAT_1: 11;
end;
A41: (
max+ h) is E
-measurable by
A6,
MESFUNC2: 25,
MESFUNC2: 34;
for x be
object st x
in (
dom (
max- h)) holds
0.
<= ((
max- h)
. x) by
MESFUNC2: 13;
then
A42: (
max- h) is
nonnegative by
SUPINF_2: 52;
A43: for n be
Nat holds (F
. n) is E
-measurable
proof
let n be
Nat;
(F
. n)
is_integrable_on M by
A3;
then
consider A be
Element of S such that
AA: A
= (
dom (F
. n)) & (F
. n) is A
-measurable;
for r be
Real holds (E
/\ (
less_dom ((F
. n),r)))
in S
proof
let r be
Real;
E
= (
dom (F
. n)) by
A2,
MESFUNC8:def 2;
then E
= A by
AA;
hence thesis by
AA;
end;
hence thesis;
end;
((F
^\ N1)
.
0 )
= (F
. (
0
+ N)) by
NAT_1:def 3;
then
A45: (
dom ((F
^\ N1)
.
0 ))
= E by
A2,
MESFUNC8:def 2;
A46:
now
let x be
Element of X;
assume x
in (
dom f);
then
A47: x
in (
dom (F
.
0 )) by
A4;
then
A48: x
in (
dom (
lim F)) by
MESFUNC8:def 9;
(
lim (F
# x))
= (f
. x) by
A4,
A47,
Th20;
hence ((
lim F)
. x)
= (f
. x) by
A48,
MESFUNC8:def 9;
end;
(
dom f)
= (
dom (F
.
0 )) by
A4;
then (
dom (
lim F))
= (
dom f) by
MESFUNC8:def 9;
then
A49: (
lim F)
= f by
A46,
PARTFUN1: 5;
(F
. N)
is_integrable_on M by
A3;
then
A51: AFN
is_integrable_on M by
MESFUNC5: 100;
deffunc
I(
Nat) = (
Integral (M,(F
. $1)));
A52: (1
*
+infty )
=
+infty by
XXREAL_3:def 5;
A53:
now
let x be
Element of X;
assume x
in (
dom h);
then
A54: x
in (
dom
|.h.|) by
MESFUNC1:def 10;
0
<= (h
. x) by
A10,
SUPINF_2: 51;
then
|.(h
. x).|
= (h
. x) by
EXTREAL1:def 1;
hence (
|.h.|
. x)
= (h
. x) by
A54,
MESFUNC1:def 10;
end;
(
dom h)
= (
dom
|.h.|) by
MESFUNC1:def 10;
then
A55: h
=
|.h.| by
A53,
PARTFUN1: 5;
(
Integral (M,h))
= (
integral+ (M,h)) by
A6,
A10,
MESFUNC5: 89;
then (
integral+ (M,h))
= (jj
* (M
. (
dom h))) by
A7,
A8,
A11,
MESFUNC5: 104;
then
A56: (
integral+ (M,
|.h.|))
<
+infty by
A1,
A7,
A55,
A52,
XXREAL_3: 72;
A57: for n be
Nat holds ((F
^\ N1)
. n) is E
-measurable
proof
let n be
Nat;
((F
^\ N1)
. n)
= (F
. (n
+ N)) by
NAT_1:def 3;
hence thesis by
A43;
end;
A58: for x be
Element of X st x
in E holds ((F
^\ N1)
# x) is
convergent & (
lim (F
# x))
= (
lim ((F
^\ N1)
# x))
proof
let x be
Element of X;
A59:
now
let n be
Element of
NAT ;
(((F
^\ N1)
# x)
. n)
= (((F
^\ N1)
. n)
. x) by
MESFUNC5:def 13;
then (((F
^\ N1)
# x)
. n)
= ((F
. (n
+ N))
. x) by
NAT_1:def 3;
then (((F
^\ N1)
# x)
. n)
= ((F
# x)
. (n
+ N)) by
MESFUNC5:def 13;
hence (((F
^\ N1)
# x)
. n)
= (((F
# x)
^\ N1)
. n) by
NAT_1:def 3;
end;
assume x
in E;
then
A60: (F
# x) is
convergent by
A2,
A4,
Th20;
then ((F
# x)
^\ N1) is
convergent by
RINFSUP2: 21;
hence ((F
^\ N1)
# x) is
convergent by
A59,
FUNCT_2: 63;
(
lim (F
# x))
= (
lim ((F
# x)
^\ N1)) by
A60,
RINFSUP2: 21;
hence thesis by
A59,
FUNCT_2: 63;
end;
then for x be
Element of X st x
in E holds ((F
^\ N1)
# x) is
convergent;
then
A61: (
lim (F
^\ N1)) is E
-measurable by
A57,
A45,
MESFUNC8: 25;
(
dom (
lim (F
^\ N1)))
= E by
A45,
MESFUNC8:def 9;
then
A62: (
dom (
lim F))
= (
dom (
lim (F
^\ N1))) by
A2,
MESFUNC8:def 9;
A63:
now
let x be
Element of X;
assume
A64: x
in (
dom (
lim F));
then x
in E by
A2,
MESFUNC8:def 9;
then
A65: (
lim (F
# x))
= (
lim ((F
^\ N1)
# x)) by
A58;
(
lim ((F
^\ N1)
# x))
= ((
lim (F
^\ N1))
. x) by
A62,
A64,
MESFUNC8:def 9;
hence ((
lim F)
. x)
= ((
lim (F
^\ N1))
. x) by
A64,
A65,
MESFUNC8:def 9;
end;
A66: (
dom (
max- h))
= (
dom h) by
MESFUNC2:def 3;
then
A67: ((
max- h)
| E)
= (
max- h) by
A7,
RELAT_1: 68;
A68: (
dom (
max+ h))
= (
dom h) by
MESFUNC2:def 2;
then
A69: ((
max+ h)
| E)
= (
max+ h) by
A7,
RELAT_1: 68;
for x be
object st x
in (
dom (
max+ h)) holds
0.
<= ((
max+ h)
. x) by
MESFUNC2: 12;
then
A70: (
max+ h) is
nonnegative by
SUPINF_2: 52;
then (
dom ((
max+ h)
+ (
max- h)))
= ((
dom (
max+ h))
/\ (
dom (
max- h))) by
A42,
MESFUNC5: 22;
then ex C be
Element of S st C
= E & (
integral+ (M,((
max+ h)
+ (
max- h))))
= ((
integral+ (M,((
max+ h)
| C)))
+ (
integral+ (M,((
max- h)
| C)))) by
A7,
A41,
A9,
A70,
A42,
A68,
A66,
MESFUNC5: 78;
then
A71: (
integral+ (M,
|.h.|))
= ((
integral+ (M,(
max+ h)))
+ (
integral+ (M,(
max- h)))) by
A69,
A67,
MESFUNC2: 24;
A72: h is E
-measurable by
A6,
MESFUNC2: 34;
then
0
<= (
integral+ (M,(
max- h))) by
A7,
A42,
A66,
MESFUNC2: 26,
MESFUNC5: 79;
then (
integral+ (M,(
max+ h)))
<>
+infty by
A71,
A56,
XXREAL_3:def 2;
then
A73: (
integral+ (M,(
max+ h)))
<
+infty by
XXREAL_0: 4;
0
<= (
integral+ (M,(
max+ h))) by
A7,
A72,
A70,
A68,
MESFUNC2: 25,
MESFUNC5: 79;
then (
integral+ (M,(
max- h)))
<>
+infty by
A71,
A56,
XXREAL_3:def 2;
then (
integral+ (M,(
max- h)))
<
+infty by
XXREAL_0: 4;
then h
is_integrable_on M by
A7,
A72,
A73;
then
A74: (AFN
+ h)
is_integrable_on M by
A51,
MESFUNC5: 108;
A75: E
= (
dom AFN) by
A2,
A12,
MESFUNC8:def 2;
then
A76:
|.(
lim_inf (F
^\ N1)).|
is_integrable_on M by
A7,
A74,
A14,
A39,
A57,
A45,
Th16;
(AFN
+ h) is
nonnegative by
A10,
A13,
MESFUNC5: 22;
then
consider J be
ExtREAL_sequence such that
A77: for n be
Nat holds (J
. n)
= (
Integral (M,((F
^\ N1)
. n))) and (
lim_inf J)
>= (
Integral (M,(
lim_inf (F
^\ N1)))) and (
lim_sup J)
<= (
Integral (M,(
lim_sup (F
^\ N1)))) and
A78: (for x be
Element of X st x
in E holds ((F
^\ N1)
# x) is
convergent) implies J is
convergent & (
lim J)
= (
Integral (M,(
lim (F
^\ N1)))) by
A7,
A74,
A14,
A75,
A39,
A57,
A45,
Th17;
consider I be
sequence of
ExtREAL such that
A79: for n be
Element of
NAT holds (I
. n)
=
I(n) from
FUNCT_2:sch 4;
reconsider I as
ExtREAL_sequence;
A80: (
dom (
lim_inf (F
^\ N1)))
= (
dom ((F
^\ N1)
.
0 )) by
MESFUNC8:def 7;
A81:
now
let x be
Element of X;
assume
A82: x
in (
dom (
lim (F
^\ N1)));
then x
in E by
A45,
MESFUNC8:def 9;
then ((F
^\ N1)
# x) is
convergent by
A58;
hence ((
lim (F
^\ N1))
. x)
= ((
lim_inf (F
^\ N1))
. x) by
A82,
MESFUNC8: 14;
end;
(
dom (
lim (F
^\ N1)))
= (
dom ((F
^\ N1)
.
0 )) by
MESFUNC8:def 9;
then (
lim (F
^\ N1))
= (
lim_inf (F
^\ N1)) by
A80,
A81,
PARTFUN1: 5;
then
A83: (
lim (F
^\ N1))
is_integrable_on M by
A45,
A76,
A80,
A61,
MESFUNC5: 100;
A84: for n be
Nat holds (I
. n)
= (
Integral (M,(F
. n)))
proof
let n be
Nat;
n
in
NAT by
ORDINAL1:def 12;
hence thesis by
A79;
end;
now
let n be
Element of
NAT ;
A85: ((F
^\ N1)
. n)
= (F
. (n
+ N)) by
NAT_1:def 3;
A86: ((I
^\ N1)
. n)
= (I
. (n
+ N)) by
NAT_1:def 3;
reconsider nn = (n
+ N) as
Element of
NAT by
ORDINAL1:def 12;
thus (J
. n)
= (
Integral (M,((F
^\ N1)
. n))) by
A77
.= (I
. nn) by
A79,
A85
.= ((I
^\ N1)
. n) by
A86;
end;
then
A87: J
= (I
^\ N1) by
FUNCT_2: 63;
then
A88: I is
convergent by
A58,
A78,
RINFSUP2: 17;
(
lim I)
= (
lim J) by
A58,
A78,
A87,
RINFSUP2: 17;
then (
lim I)
= (
Integral (M,(
lim F))) by
A58,
A62,
A63,
A78,
PARTFUN1: 5;
hence thesis by
A49,
A62,
A63,
A83,
A84,
A88,
PARTFUN1: 5;
end;