parsp_2.miz



    begin

    

     Lm1: for F be add-associative right_zeroed right_complementable non empty addLoopStr, a,b be Element of F holds (a - b) = ( 0. F) implies a = b

    proof

      let F be add-associative right_zeroed right_complementable non empty addLoopStr, a,b be Element of F;

      assume (a - b) = ( 0. F);

      then (a + ( - b)) = ( 0. F) by RLVECT_1:def 11;

      then a = ( - ( - b)) by RLVECT_1: 6;

      hence thesis by RLVECT_1: 17;

    end;

    

     Lm2: for F be add-associative right_zeroed right_complementable non empty addLoopStr, x,y be Element of F holds ((x + ( - y)) = ( 0. F) iff x = y) & ((x - y) = ( 0. F) iff x = y)

    proof

      let F be add-associative right_zeroed right_complementable non empty addLoopStr, x,y be Element of F;

      

       A1: (x + ( - y)) = ( 0. F) implies x = y

      proof

        assume (x + ( - y)) = ( 0. F);

        then (x + (( - y) + y)) = (( 0. F) + y) by RLVECT_1:def 3;

        then (x + ( 0. F)) = (( 0. F) + y) by RLVECT_1: 5;

        then x = (( 0. F) + y) by RLVECT_1: 4;

        hence thesis by RLVECT_1: 4;

      end;

      

       A2: (x - y) = ( 0. F) implies x = y

      proof

        assume (x - y) = ( 0. F);

        then ((x + ( - y)) + y) = (( 0. F) + y) by RLVECT_1:def 11;

        then (x + (( - y) + y)) = (( 0. F) + y) by RLVECT_1:def 3;

        then (x + ( 0. F)) = (( 0. F) + y) by RLVECT_1: 5;

        then x = (( 0. F) + y) by RLVECT_1: 4;

        hence thesis by RLVECT_1: 4;

      end;

      x = y implies (x - y) = ( 0. F)

      proof

        assume x = y;

        then (x - y) = (y + ( - y)) by RLVECT_1:def 11;

        hence thesis by RLVECT_1: 5;

      end;

      hence thesis by A1, A2, RLVECT_1: 5;

    end;

    reserve F for Field;

    theorem :: PARSP_2:1

    

     Th1: ( MPS F) is ParSp

    proof

      for a,b,c,d,p,q,r,s be Element of ( MPS F) holds (a,b) '||' (b,a) & (a,b) '||' (c,c) & ((a,b) '||' (p,q) & (a,b) '||' (r,s) implies (p,q) '||' (r,s) or a = b) & ((a,b) '||' (a,c) implies (b,a) '||' (b,c)) & ex x be Element of ( MPS F) st (a,b) '||' (c,x) & (a,c) '||' (b,x) by PARSP_1: 13, PARSP_1: 14, PARSP_1: 15, PARSP_1: 16, PARSP_1: 17;

      hence thesis by PARSP_1:def 12;

    end;

    reserve a,b,c,d,p,q,r for Element of ( MPS F);

    reserve e,f,g,h,i,j,k,l,m,n,o,w for Element of [:the carrier of F, the carrier of F, the carrier of F:];

    reserve K,L,M,N,R,S for Element of F;

    

     Lm3: ((((e `1_3 ) - (f `1_3 )) * ((g `2_3 ) - (h `2_3 ))) - (((g `1_3 ) - (h `1_3 )) * ((e `2_3 ) - (f `2_3 )))) = ( 0. F) & ((((e `1_3 ) - (f `1_3 )) * ((g `3_3 ) - (h `3_3 ))) - (((g `1_3 ) - (h `1_3 )) * ((e `3_3 ) - (f `3_3 )))) = ( 0. F) & ((((e `2_3 ) - (f `2_3 )) * ((g `3_3 ) - (h `3_3 ))) - (((g `2_3 ) - (h `2_3 )) * ((e `3_3 ) - (f `3_3 )))) = ( 0. F) iff (ex K st (K * ((e `1_3 ) - (f `1_3 ))) = ((g `1_3 ) - (h `1_3 )) & (K * ((e `2_3 ) - (f `2_3 ))) = ((g `2_3 ) - (h `2_3 )) & (K * ((e `3_3 ) - (f `3_3 ))) = ((g `3_3 ) - (h `3_3 ))) or ((e `1_3 ) - (f `1_3 )) = ( 0. F) & ((e `2_3 ) - (f `2_3 )) = ( 0. F) & ((e `3_3 ) - (f `3_3 )) = ( 0. F)

    proof

      

       A1: ((((e `1_3 ) - (f `1_3 )) * ((g `2_3 ) - (h `2_3 ))) - (((g `1_3 ) - (h `1_3 )) * ((e `2_3 ) - (f `2_3 )))) = ( 0. F) & ((((e `1_3 ) - (f `1_3 )) * ((g `3_3 ) - (h `3_3 ))) - (((g `1_3 ) - (h `1_3 )) * ((e `3_3 ) - (f `3_3 )))) = ( 0. F) & ((((e `2_3 ) - (f `2_3 )) * ((g `3_3 ) - (h `3_3 ))) - (((g `2_3 ) - (h `2_3 )) * ((e `3_3 ) - (f `3_3 )))) = ( 0. F) implies (ex K st (K * ((e `1_3 ) - (f `1_3 ))) = ((g `1_3 ) - (h `1_3 )) & (K * ((e `2_3 ) - (f `2_3 ))) = ((g `2_3 ) - (h `2_3 )) & (K * ((e `3_3 ) - (f `3_3 ))) = ((g `3_3 ) - (h `3_3 ))) or ((e `1_3 ) - (f `1_3 )) = ( 0. F) & ((e `2_3 ) - (f `2_3 )) = ( 0. F) & ((e `3_3 ) - (f `3_3 )) = ( 0. F)

      proof

        assume that

         A2: ((((e `1_3 ) - (f `1_3 )) * ((g `2_3 ) - (h `2_3 ))) - (((g `1_3 ) - (h `1_3 )) * ((e `2_3 ) - (f `2_3 )))) = ( 0. F) and

         A3: ((((e `1_3 ) - (f `1_3 )) * ((g `3_3 ) - (h `3_3 ))) - (((g `1_3 ) - (h `1_3 )) * ((e `3_3 ) - (f `3_3 )))) = ( 0. F) and

         A4: ((((e `2_3 ) - (f `2_3 )) * ((g `3_3 ) - (h `3_3 ))) - (((g `2_3 ) - (h `2_3 )) * ((e `3_3 ) - (f `3_3 )))) = ( 0. F);

        now

           A5:

          now

            assume

             A6: ((e `3_3 ) - (f `3_3 )) <> ( 0. F);

            

             A7: ((((g `3_3 ) - (h `3_3 )) * (((e `3_3 ) - (f `3_3 )) " )) * ((e `3_3 ) - (f `3_3 ))) = (((g `3_3 ) - (h `3_3 )) * ((((e `3_3 ) - (f `3_3 )) " ) * ((e `3_3 ) - (f `3_3 )))) by GROUP_1:def 3

            .= (((g `3_3 ) - (h `3_3 )) * ( 1_ F)) by A6, VECTSP_1:def 10

            .= ((g `3_3 ) - (h `3_3 ));

            

             A8: ((((g `3_3 ) - (h `3_3 )) * (((e `3_3 ) - (f `3_3 )) " )) * ((e `2_3 ) - (f `2_3 ))) = ((((e `2_3 ) - (f `2_3 )) * ((g `3_3 ) - (h `3_3 ))) * (((e `3_3 ) - (f `3_3 )) " )) by GROUP_1:def 3

            .= ((((g `2_3 ) - (h `2_3 )) * ((e `3_3 ) - (f `3_3 ))) * (((e `3_3 ) - (f `3_3 )) " )) by A4, Lm1

            .= (((g `2_3 ) - (h `2_3 )) * (((e `3_3 ) - (f `3_3 )) * (((e `3_3 ) - (f `3_3 )) " ))) by GROUP_1:def 3

            .= (((g `2_3 ) - (h `2_3 )) * ( 1_ F)) by A6, VECTSP_1:def 10

            .= ((g `2_3 ) - (h `2_3 ));

            ((((g `3_3 ) - (h `3_3 )) * (((e `3_3 ) - (f `3_3 )) " )) * ((e `1_3 ) - (f `1_3 ))) = ((((e `1_3 ) - (f `1_3 )) * ((g `3_3 ) - (h `3_3 ))) * (((e `3_3 ) - (f `3_3 )) " )) by GROUP_1:def 3

            .= ((((g `1_3 ) - (h `1_3 )) * ((e `3_3 ) - (f `3_3 ))) * (((e `3_3 ) - (f `3_3 )) " )) by A3, Lm1

            .= (((g `1_3 ) - (h `1_3 )) * (((e `3_3 ) - (f `3_3 )) * (((e `3_3 ) - (f `3_3 )) " ))) by GROUP_1:def 3

            .= (((g `1_3 ) - (h `1_3 )) * ( 1_ F)) by A6, VECTSP_1:def 10

            .= ((g `1_3 ) - (h `1_3 ));

            hence thesis by A8, A7;

          end;

           A9:

          now

            assume

             A10: ((e `2_3 ) - (f `2_3 )) <> ( 0. F);

            

             A11: ((((g `2_3 ) - (h `2_3 )) * (((e `2_3 ) - (f `2_3 )) " )) * ((e `2_3 ) - (f `2_3 ))) = (((g `2_3 ) - (h `2_3 )) * ((((e `2_3 ) - (f `2_3 )) " ) * ((e `2_3 ) - (f `2_3 )))) by GROUP_1:def 3

            .= (((g `2_3 ) - (h `2_3 )) * ( 1_ F)) by A10, VECTSP_1:def 10

            .= ((g `2_3 ) - (h `2_3 ));

            

             A12: ((((g `2_3 ) - (h `2_3 )) * (((e `2_3 ) - (f `2_3 )) " )) * ((e `3_3 ) - (f `3_3 ))) = ((((e `2_3 ) - (f `2_3 )) " ) * (((g `2_3 ) - (h `2_3 )) * ((e `3_3 ) - (f `3_3 )))) by GROUP_1:def 3

            .= ((((e `2_3 ) - (f `2_3 )) " ) * (((e `2_3 ) - (f `2_3 )) * ((g `3_3 ) - (h `3_3 )))) by A4, Lm1

            .= (((((e `2_3 ) - (f `2_3 )) " ) * ((e `2_3 ) - (f `2_3 ))) * ((g `3_3 ) - (h `3_3 ))) by GROUP_1:def 3

            .= (((g `3_3 ) - (h `3_3 )) * ( 1_ F)) by A10, VECTSP_1:def 10

            .= ((g `3_3 ) - (h `3_3 ));

            ((((g `2_3 ) - (h `2_3 )) * (((e `2_3 ) - (f `2_3 )) " )) * ((e `1_3 ) - (f `1_3 ))) = ((((e `1_3 ) - (f `1_3 )) * ((g `2_3 ) - (h `2_3 ))) * (((e `2_3 ) - (f `2_3 )) " )) by GROUP_1:def 3

            .= ((((g `1_3 ) - (h `1_3 )) * ((e `2_3 ) - (f `2_3 ))) * (((e `2_3 ) - (f `2_3 )) " )) by A2, Lm1

            .= (((g `1_3 ) - (h `1_3 )) * (((e `2_3 ) - (f `2_3 )) * (((e `2_3 ) - (f `2_3 )) " ))) by GROUP_1:def 3

            .= (((g `1_3 ) - (h `1_3 )) * ( 1_ F)) by A10, VECTSP_1:def 10

            .= ((g `1_3 ) - (h `1_3 ));

            hence thesis by A11, A12;

          end;

          now

            assume

             A13: ((e `1_3 ) - (f `1_3 )) <> ( 0. F);

            

             A14: ((((g `1_3 ) - (h `1_3 )) * (((e `1_3 ) - (f `1_3 )) " )) * ((e `1_3 ) - (f `1_3 ))) = (((g `1_3 ) - (h `1_3 )) * ((((e `1_3 ) - (f `1_3 )) " ) * ((e `1_3 ) - (f `1_3 )))) by GROUP_1:def 3

            .= (((g `1_3 ) - (h `1_3 )) * ( 1_ F)) by A13, VECTSP_1:def 10

            .= ((g `1_3 ) - (h `1_3 ));

            

             A15: ((((g `1_3 ) - (h `1_3 )) * (((e `1_3 ) - (f `1_3 )) " )) * ((e `3_3 ) - (f `3_3 ))) = ((((e `1_3 ) - (f `1_3 )) " ) * (((g `1_3 ) - (h `1_3 )) * ((e `3_3 ) - (f `3_3 )))) by GROUP_1:def 3

            .= ((((e `1_3 ) - (f `1_3 )) " ) * (((e `1_3 ) - (f `1_3 )) * ((g `3_3 ) - (h `3_3 )))) by A3, Lm1

            .= (((((e `1_3 ) - (f `1_3 )) " ) * ((e `1_3 ) - (f `1_3 ))) * ((g `3_3 ) - (h `3_3 ))) by GROUP_1:def 3

            .= (((g `3_3 ) - (h `3_3 )) * ( 1_ F)) by A13, VECTSP_1:def 10

            .= ((g `3_3 ) - (h `3_3 ));

            ((((g `1_3 ) - (h `1_3 )) * (((e `1_3 ) - (f `1_3 )) " )) * ((e `2_3 ) - (f `2_3 ))) = ((((e `1_3 ) - (f `1_3 )) " ) * (((g `1_3 ) - (h `1_3 )) * ((e `2_3 ) - (f `2_3 )))) by GROUP_1:def 3

            .= ((((e `1_3 ) - (f `1_3 )) " ) * (((e `1_3 ) - (f `1_3 )) * ((g `2_3 ) - (h `2_3 )))) by A2, Lm1

            .= (((((e `1_3 ) - (f `1_3 )) " ) * ((e `1_3 ) - (f `1_3 ))) * ((g `2_3 ) - (h `2_3 ))) by GROUP_1:def 3

            .= (((g `2_3 ) - (h `2_3 )) * ( 1_ F)) by A13, VECTSP_1:def 10

            .= ((g `2_3 ) - (h `2_3 ));

            hence thesis by A14, A15;

          end;

          hence thesis by A9, A5;

        end;

        hence thesis;

      end;

      (ex K st (K * ((e `1_3 ) - (f `1_3 ))) = ((g `1_3 ) - (h `1_3 )) & (K * ((e `2_3 ) - (f `2_3 ))) = ((g `2_3 ) - (h `2_3 )) & (K * ((e `3_3 ) - (f `3_3 ))) = ((g `3_3 ) - (h `3_3 ))) or ((e `1_3 ) - (f `1_3 )) = ( 0. F) & ((e `2_3 ) - (f `2_3 )) = ( 0. F) & ((e `3_3 ) - (f `3_3 )) = ( 0. F) implies ((((e `1_3 ) - (f `1_3 )) * ((g `2_3 ) - (h `2_3 ))) - (((g `1_3 ) - (h `1_3 )) * ((e `2_3 ) - (f `2_3 )))) = ( 0. F) & ((((e `1_3 ) - (f `1_3 )) * ((g `3_3 ) - (h `3_3 ))) - (((g `1_3 ) - (h `1_3 )) * ((e `3_3 ) - (f `3_3 )))) = ( 0. F) & ((((e `2_3 ) - (f `2_3 )) * ((g `3_3 ) - (h `3_3 ))) - (((g `2_3 ) - (h `2_3 )) * ((e `3_3 ) - (f `3_3 )))) = ( 0. F)

      proof

         A16:

        now

          given K such that

           A17: (K * ((e `1_3 ) - (f `1_3 ))) = ((g `1_3 ) - (h `1_3 )) and

           A18: (K * ((e `2_3 ) - (f `2_3 ))) = ((g `2_3 ) - (h `2_3 )) & (K * ((e `3_3 ) - (f `3_3 ))) = ((g `3_3 ) - (h `3_3 ));

          

           A19: ((((e `2_3 ) - (f `2_3 )) * ((g `3_3 ) - (h `3_3 ))) - (((g `2_3 ) - (h `2_3 )) * ((e `3_3 ) - (f `3_3 )))) = (((K * ((e `2_3 ) - (f `2_3 ))) * ((e `3_3 ) - (f `3_3 ))) - ((K * ((e `2_3 ) - (f `2_3 ))) * ((e `3_3 ) - (f `3_3 )))) by A18, GROUP_1:def 3;

          ((((e `1_3 ) - (f `1_3 )) * ((g `2_3 ) - (h `2_3 ))) - (((g `1_3 ) - (h `1_3 )) * ((e `2_3 ) - (f `2_3 )))) = (((K * ((e `1_3 ) - (f `1_3 ))) * ((e `2_3 ) - (f `2_3 ))) - ((K * ((e `1_3 ) - (f `1_3 ))) * ((e `2_3 ) - (f `2_3 )))) & ((((e `1_3 ) - (f `1_3 )) * ((g `3_3 ) - (h `3_3 ))) - (((g `1_3 ) - (h `1_3 )) * ((e `3_3 ) - (f `3_3 )))) = (((K * ((e `1_3 ) - (f `1_3 ))) * ((e `3_3 ) - (f `3_3 ))) - ((K * ((e `1_3 ) - (f `1_3 ))) * ((e `3_3 ) - (f `3_3 )))) by A17, A18, GROUP_1:def 3;

          hence thesis by A19, RLVECT_1: 15;

        end;

        

         A20: ((e `1_3 ) - (f `1_3 )) = ( 0. F) & ((e `2_3 ) - (f `2_3 )) = ( 0. F) & ((e `3_3 ) - (f `3_3 )) = ( 0. F) implies thesis by RLVECT_1: 15;

        assume (ex K st (K * ((e `1_3 ) - (f `1_3 ))) = ((g `1_3 ) - (h `1_3 )) & (K * ((e `2_3 ) - (f `2_3 ))) = ((g `2_3 ) - (h `2_3 )) & (K * ((e `3_3 ) - (f `3_3 ))) = ((g `3_3 ) - (h `3_3 ))) or ((e `1_3 ) - (f `1_3 )) = ( 0. F) & ((e `2_3 ) - (f `2_3 )) = ( 0. F) & ((e `3_3 ) - (f `3_3 )) = ( 0. F);

        hence thesis by A20, A16;

      end;

      hence thesis by A1;

    end;

    theorem :: PARSP_2:2

    

     Th2: (a,b) '||' (c,d) iff ex e, f, g, h st [ [a, b], [c, d]] = [ [e, f], [g, h]] & ((ex K st (K * ((e `1_3 ) - (f `1_3 ))) = ((g `1_3 ) - (h `1_3 )) & (K * ((e `2_3 ) - (f `2_3 ))) = ((g `2_3 ) - (h `2_3 )) & (K * ((e `3_3 ) - (f `3_3 ))) = ((g `3_3 ) - (h `3_3 ))) or ((e `1_3 ) - (f `1_3 )) = ( 0. F) & ((e `2_3 ) - (f `2_3 )) = ( 0. F) & ((e `3_3 ) - (f `3_3 )) = ( 0. F))

    proof

      

       A1: (a,b) '||' (c,d) implies ex e, f, g, h st [ [a, b], [c, d]] = [ [e, f], [g, h]] & ((ex K st (K * ((e `1_3 ) - (f `1_3 ))) = ((g `1_3 ) - (h `1_3 )) & (K * ((e `2_3 ) - (f `2_3 ))) = ((g `2_3 ) - (h `2_3 )) & (K * ((e `3_3 ) - (f `3_3 ))) = ((g `3_3 ) - (h `3_3 ))) or ((e `1_3 ) - (f `1_3 )) = ( 0. F) & ((e `2_3 ) - (f `2_3 )) = ( 0. F) & ((e `3_3 ) - (f `3_3 )) = ( 0. F))

      proof

        assume (a,b) '||' (c,d);

        then

        consider e, f, g, h such that

         A2: [ [a, b], [c, d]] = [ [e, f], [g, h]] and

         A3: ((((e `1_3 ) - (f `1_3 )) * ((g `2_3 ) - (h `2_3 ))) - (((g `1_3 ) - (h `1_3 )) * ((e `2_3 ) - (f `2_3 )))) = ( 0. F) & ((((e `1_3 ) - (f `1_3 )) * ((g `3_3 ) - (h `3_3 ))) - (((g `1_3 ) - (h `1_3 )) * ((e `3_3 ) - (f `3_3 )))) = ( 0. F) & ((((e `2_3 ) - (f `2_3 )) * ((g `3_3 ) - (h `3_3 ))) - (((g `2_3 ) - (h `2_3 )) * ((e `3_3 ) - (f `3_3 )))) = ( 0. F) by PARSP_1: 12;

        (ex K st (K * ((e `1_3 ) - (f `1_3 ))) = ((g `1_3 ) - (h `1_3 )) & (K * ((e `2_3 ) - (f `2_3 ))) = ((g `2_3 ) - (h `2_3 )) & (K * ((e `3_3 ) - (f `3_3 ))) = ((g `3_3 ) - (h `3_3 ))) or ((e `1_3 ) - (f `1_3 )) = ( 0. F) & ((e `2_3 ) - (f `2_3 )) = ( 0. F) & ((e `3_3 ) - (f `3_3 )) = ( 0. F) by A3, Lm3;

        hence thesis by A2;

      end;

      (ex e, f, g, h st [ [a, b], [c, d]] = [ [e, f], [g, h]] & ((ex K st (K * ((e `1_3 ) - (f `1_3 ))) = ((g `1_3 ) - (h `1_3 )) & (K * ((e `2_3 ) - (f `2_3 ))) = ((g `2_3 ) - (h `2_3 )) & (K * ((e `3_3 ) - (f `3_3 ))) = ((g `3_3 ) - (h `3_3 ))) or (((e `1_3 ) - (f `1_3 )) = ( 0. F) & ((e `2_3 ) - (f `2_3 )) = ( 0. F) & ((e `3_3 ) - (f `3_3 )) = ( 0. F)))) implies (a,b) '||' (c,d)

      proof

        given e, f, g, h such that

         A4: [ [a, b], [c, d]] = [ [e, f], [g, h]] and

         A5: (ex K st (K * ((e `1_3 ) - (f `1_3 ))) = ((g `1_3 ) - (h `1_3 )) & (K * ((e `2_3 ) - (f `2_3 ))) = ((g `2_3 ) - (h `2_3 )) & (K * ((e `3_3 ) - (f `3_3 ))) = ((g `3_3 ) - (h `3_3 ))) or ((e `1_3 ) - (f `1_3 )) = ( 0. F) & ((e `2_3 ) - (f `2_3 )) = ( 0. F) & ((e `3_3 ) - (f `3_3 )) = ( 0. F);

        

         A6: ((((e `2_3 ) - (f `2_3 )) * ((g `3_3 ) - (h `3_3 ))) - (((g `2_3 ) - (h `2_3 )) * ((e `3_3 ) - (f `3_3 )))) = ( 0. F) by A5, Lm3;

        ((((e `1_3 ) - (f `1_3 )) * ((g `2_3 ) - (h `2_3 ))) - (((g `1_3 ) - (h `1_3 )) * ((e `2_3 ) - (f `2_3 )))) = ( 0. F) & ((((e `1_3 ) - (f `1_3 )) * ((g `3_3 ) - (h `3_3 ))) - (((g `1_3 ) - (h `1_3 )) * ((e `3_3 ) - (f `3_3 )))) = ( 0. F) by A5, Lm3;

        hence thesis by A4, A6, PARSP_1: 12;

      end;

      hence thesis by A1;

    end;

    theorem :: PARSP_2:3

    

     Th3: not (a,b) '||' (a,c) & [ [a, b], [a, c]] = [ [e, f], [e, g]] implies e <> f & e <> g & f <> g

    proof

      assume

       A1: ( not (a,b) '||' (a,c)) & [ [a, b], [a, c]] = [ [e, f], [e, g]];

      then (( 0. F) * ((e `1_3 ) - (f `1_3 ))) <> ((e `1_3 ) - (g `1_3 )) or (( 0. F) * ((e `2_3 ) - (f `2_3 ))) <> ((e `2_3 ) - (g `2_3 )) or (( 0. F) * ((e `3_3 ) - (f `3_3 ))) <> ((e `3_3 ) - (g `3_3 )) by Th2;

      then

       A2: ( 0. F) <> ((e `1_3 ) - (g `1_3 )) or ( 0. F) <> ((e `2_3 ) - (g `2_3 )) or ( 0. F) <> ((e `3_3 ) - (g `3_3 ));

      

       A3: f <> g

      proof

        assume

         A4: not thesis;

        (((e `1_3 ) - (f `1_3 )) * ( 1_ F)) <> ((e `1_3 ) - (g `1_3 )) or (((e `2_3 ) - (f `2_3 )) * ( 1_ F)) <> ((e `2_3 ) - (g `2_3 )) or (((e `3_3 ) - (f `3_3 )) * ( 1_ F)) <> ((e `3_3 ) - (g `3_3 )) by A1, Th2;

        hence contradiction by A4;

      end;

      ((e `1_3 ) - (f `1_3 )) <> ( 0. F) or ((e `2_3 ) - (f `2_3 )) <> ( 0. F) or ((e `3_3 ) - (f `3_3 )) <> ( 0. F) by A1, Th2;

      hence thesis by A2, A3, RLVECT_1: 15;

    end;

    theorem :: PARSP_2:4

    

     Th4: not (a,b) '||' (a,c) & [ [a, b], [a, c]] = [ [e, f], [e, g]] & (K * ((e `1_3 ) - (f `1_3 ))) = (L * ((e `1_3 ) - (g `1_3 ))) & (K * ((e `2_3 ) - (f `2_3 ))) = (L * ((e `2_3 ) - (g `2_3 ))) & (K * ((e `3_3 ) - (f `3_3 ))) = (L * ((e `3_3 ) - (g `3_3 ))) implies K = ( 0. F) & L = ( 0. F)

    proof

      assume that

       A1: ( not (a,b) '||' (a,c)) & [ [a, b], [a, c]] = [ [e, f], [e, g]] and

       A2: (K * ((e `1_3 ) - (f `1_3 ))) = (L * ((e `1_3 ) - (g `1_3 ))) and

       A3: (K * ((e `2_3 ) - (f `2_3 ))) = (L * ((e `2_3 ) - (g `2_3 ))) and

       A4: (K * ((e `3_3 ) - (f `3_3 ))) = (L * ((e `3_3 ) - (g `3_3 )));

      e = [(e `1_3 ), (e `2_3 ), (e `3_3 )] & g = [(g `1_3 ), (g `2_3 ), (g `3_3 )];

      then (e `1_3 ) <> (g `1_3 ) or (e `2_3 ) <> (g `2_3 ) or (e `3_3 ) <> (g `3_3 ) by A1, Th3;

      then

       A5: ((e `1_3 ) - (g `1_3 )) <> ( 0. F) or ((e `2_3 ) - (g `2_3 )) <> ( 0. F) or ((e `3_3 ) - (g `3_3 )) <> ( 0. F) by Lm2;

      ((K * ((e `1_3 ) - (f `1_3 ))) * ((e `2_3 ) - (g `2_3 ))) = (L * (((e `1_3 ) - (g `1_3 )) * ((e `2_3 ) - (g `2_3 )))) & ((K * ((e `2_3 ) - (f `2_3 ))) * ((e `1_3 ) - (g `1_3 ))) = (L * (((e `2_3 ) - (g `2_3 )) * ((e `1_3 ) - (g `1_3 )))) by A2, A3, GROUP_1:def 3;

      then (((K * ((e `1_3 ) - (f `1_3 ))) * ((e `2_3 ) - (g `2_3 ))) - ((K * ((e `2_3 ) - (f `2_3 ))) * ((e `1_3 ) - (g `1_3 )))) = ( 0. F) by RLVECT_1: 15;

      then ((K * (((e `1_3 ) - (f `1_3 )) * ((e `2_3 ) - (g `2_3 )))) - ((K * ((e `2_3 ) - (f `2_3 ))) * ((e `1_3 ) - (g `1_3 )))) = ( 0. F) by GROUP_1:def 3;

      then ((K * (((e `1_3 ) - (f `1_3 )) * ((e `2_3 ) - (g `2_3 )))) - (K * (((e `2_3 ) - (f `2_3 )) * ((e `1_3 ) - (g `1_3 ))))) = ( 0. F) by GROUP_1:def 3;

      then

       A6: (K * ((((e `1_3 ) - (f `1_3 )) * ((e `2_3 ) - (g `2_3 ))) - (((e `1_3 ) - (g `1_3 )) * ((e `2_3 ) - (f `2_3 ))))) = ( 0. F) by VECTSP_1: 11;

      ((K * ((e `1_3 ) - (f `1_3 ))) * ((e `3_3 ) - (g `3_3 ))) = (L * (((e `1_3 ) - (g `1_3 )) * ((e `3_3 ) - (g `3_3 )))) & ((K * ((e `3_3 ) - (f `3_3 ))) * ((e `1_3 ) - (g `1_3 ))) = (L * (((e `3_3 ) - (g `3_3 )) * ((e `1_3 ) - (g `1_3 )))) by A2, A4, GROUP_1:def 3;

      then (((K * ((e `1_3 ) - (f `1_3 ))) * ((e `3_3 ) - (g `3_3 ))) - ((K * ((e `3_3 ) - (f `3_3 ))) * ((e `1_3 ) - (g `1_3 )))) = ( 0. F) by RLVECT_1: 15;

      then ((K * (((e `1_3 ) - (f `1_3 )) * ((e `3_3 ) - (g `3_3 )))) - ((K * ((e `3_3 ) - (f `3_3 ))) * ((e `1_3 ) - (g `1_3 )))) = ( 0. F) by GROUP_1:def 3;

      then ((K * (((e `1_3 ) - (f `1_3 )) * ((e `3_3 ) - (g `3_3 )))) - (K * (((e `3_3 ) - (f `3_3 )) * ((e `1_3 ) - (g `1_3 ))))) = ( 0. F) by GROUP_1:def 3;

      then

       A7: (K * ((((e `1_3 ) - (f `1_3 )) * ((e `3_3 ) - (g `3_3 ))) - (((e `1_3 ) - (g `1_3 )) * ((e `3_3 ) - (f `3_3 ))))) = ( 0. F) by VECTSP_1: 11;

      ((K * ((e `2_3 ) - (f `2_3 ))) * ((e `3_3 ) - (g `3_3 ))) = (L * (((e `2_3 ) - (g `2_3 )) * ((e `3_3 ) - (g `3_3 )))) & ((K * ((e `3_3 ) - (f `3_3 ))) * ((e `2_3 ) - (g `2_3 ))) = (L * (((e `3_3 ) - (g `3_3 )) * ((e `2_3 ) - (g `2_3 )))) by A3, A4, GROUP_1:def 3;

      then (((K * ((e `2_3 ) - (f `2_3 ))) * ((e `3_3 ) - (g `3_3 ))) - ((K * ((e `3_3 ) - (f `3_3 ))) * ((e `2_3 ) - (g `2_3 )))) = ( 0. F) by RLVECT_1: 15;

      then ((K * (((e `2_3 ) - (f `2_3 )) * ((e `3_3 ) - (g `3_3 )))) - ((K * ((e `3_3 ) - (f `3_3 ))) * ((e `2_3 ) - (g `2_3 )))) = ( 0. F) by GROUP_1:def 3;

      then ((K * (((e `2_3 ) - (f `2_3 )) * ((e `3_3 ) - (g `3_3 )))) - (K * (((e `3_3 ) - (f `3_3 )) * ((e `2_3 ) - (g `2_3 ))))) = ( 0. F) by GROUP_1:def 3;

      then

       A8: (K * ((((e `2_3 ) - (f `2_3 )) * ((e `3_3 ) - (g `3_3 ))) - (((e `2_3 ) - (g `2_3 )) * ((e `3_3 ) - (f `3_3 ))))) = ( 0. F) by VECTSP_1: 11;

      

       A9: ((((e `1_3 ) - (f `1_3 )) * ((e `2_3 ) - (g `2_3 ))) - (((e `1_3 ) - (g `1_3 )) * ((e `2_3 ) - (f `2_3 )))) <> ( 0. F) or ((((e `2_3 ) - (f `2_3 )) * ((e `3_3 ) - (g `3_3 ))) - (((e `2_3 ) - (g `2_3 )) * ((e `3_3 ) - (f `3_3 )))) <> ( 0. F) or ((((e `1_3 ) - (f `1_3 )) * ((e `3_3 ) - (g `3_3 ))) - (((e `1_3 ) - (g `1_3 )) * ((e `3_3 ) - (f `3_3 )))) <> ( 0. F) by A1, PARSP_1: 12;

      then

       A10: K = ( 0. F) by A6, A8, A7, VECTSP_1: 12;

      then

       A11: ( 0. F) = (L * ((e `3_3 ) - (g `3_3 ))) by A4;

      ( 0. F) = (L * ((e `1_3 ) - (g `1_3 ))) & ( 0. F) = (L * ((e `2_3 ) - (g `2_3 ))) by A2, A3, A10;

      hence thesis by A6, A8, A7, A9, A11, A5, VECTSP_1: 12;

    end;

    

     Lm4: for F be add-associative right_zeroed right_complementable non empty addLoopStr, a,b,c be Element of F holds ((b + a) - (c + a)) = (b - c)

    proof

      let F be add-associative right_zeroed right_complementable non empty addLoopStr, a,b,c be Element of F;

      

      thus ((b + a) - (c + a)) = ((b + a) + ( - (c + a))) by RLVECT_1:def 11

      .= ((b + a) + (( - a) + ( - c))) by RLVECT_1: 31

      .= (((b + a) + ( - a)) + ( - c)) by RLVECT_1:def 3

      .= ((b + (a + ( - a))) + ( - c)) by RLVECT_1:def 3

      .= ((b + ( 0. F)) + ( - c)) by RLVECT_1:def 10

      .= (b + ( - c)) by RLVECT_1: 4

      .= (b - c) by RLVECT_1:def 11;

    end;

    

     Lm5: ((K - L) - (R - L)) = (K - R)

    proof

      

      thus ((K - L) - (R - L)) = ((K + ( - L)) - (R - L)) by RLVECT_1:def 11

      .= ((( - L) + K) - (R + ( - L))) by RLVECT_1:def 11

      .= (K - R) by Lm4;

    end;

    

     Lm6: ((K * (N - M)) - (L * (N - S))) = (S - M) implies ((K + ( - ( 1_ F))) * (N - M)) = ((L + ( - ( 1_ F))) * (N - S))

    proof

      assume ((K * (N - M)) - (L * (N - S))) = (S - M);

      

      then ((K * (N - M)) - (L * (N - S))) = (S + ( - M)) by RLVECT_1:def 11

      .= ((S + ( - M)) + ( 0. F)) by RLVECT_1: 4

      .= ((( - M) + S) + (( - N) + N)) by RLVECT_1: 5

      .= (S + ((( - N) + N) + ( - M))) by RLVECT_1:def 3

      .= (S + (( - N) + (N + ( - M)))) by RLVECT_1:def 3

      .= (S + (( - N) + (N - M))) by RLVECT_1:def 11

      .= ((S + ( - N)) + (N - M)) by RLVECT_1:def 3

      .= ((S - N) + (N - M)) by RLVECT_1:def 11;

      then (((K * (N - M)) + ( - (L * (N - S)))) + (L * (N - S))) = (((S - N) + (N - M)) + (L * (N - S))) by RLVECT_1:def 11;

      then ((K * (N - M)) + (( - (L * (N - S))) + (L * (N - S)))) = (((S - N) + (N - M)) + (L * (N - S))) by RLVECT_1:def 3;

      then ((K * (N - M)) + ( 0. F)) = (((S - N) + (N - M)) + (L * (N - S))) by RLVECT_1: 5;

      

      then (K * (N - M)) = (((S - N) + (N - M)) + (L * (N - S))) by RLVECT_1: 4

      .= (((S - N) + (L * (N - S))) + (N - M)) by RLVECT_1:def 3;

      

      then ((K * (N - M)) + ( - (N - M))) = (((S - N) + (L * (N - S))) + ((N - M) + ( - (N - M)))) by RLVECT_1:def 3

      .= (((S - N) + (L * (N - S))) + ( 0. F)) by RLVECT_1: 5

      .= ((S - N) + (L * (N - S))) by RLVECT_1: 4

      .= ((S + ( - N)) + (L * (N - S))) by RLVECT_1:def 11

      .= ((L * (N - S)) + ( - (N - S))) by RLVECT_1: 33;

      then ((K * (N - M)) + ( - (( 1_ F) * (N - M)))) = ((L * (N - S)) + ( - (N - S)));

      then ((K * (N - M)) + (( - ( 1_ F)) * (N - M))) = ((L * (N - S)) + ( - (N - S))) by VECTSP_1: 9;

      

      then ((K + ( - ( 1_ F))) * (N - M)) = ((L * (N - S)) + ( - (N - S))) by VECTSP_1:def 7

      .= ((L * (N - S)) + ( - (( 1_ F) * (N - S))))

      .= ((L * (N - S)) + (( - ( 1_ F)) * (N - S))) by VECTSP_1: 9;

      hence thesis by VECTSP_1:def 7;

    end;

    

     Lm7: (K - L) = (N - M) implies M = ((L + N) - K)

    proof

      assume (K - L) = (N - M);

      then (M + (K + ( - L))) = (M + (N - M)) by RLVECT_1:def 11;

      then (M + (K + ( - L))) = (M + (N + ( - M))) by RLVECT_1:def 11;

      then ((M + K) + ( - L)) = (M + (N + ( - M))) by RLVECT_1:def 3;

      then ((M + K) + ( - L)) = ((M + N) + ( - M)) by RLVECT_1:def 3;

      then ((M + K) - L) = ((N + M) + ( - M)) by RLVECT_1:def 11;

      then ((M + K) - L) = (N + (M + ( - M))) by RLVECT_1:def 3;

      then ((M + K) - L) = (N + ( 0. F)) by RLVECT_1: 5;

      then (((M + K) - L) + L) = (N + L) by RLVECT_1: 4;

      then (((M + K) + ( - L)) + L) = (N + L) by RLVECT_1:def 11;

      then ((M + K) + (( - L) + L)) = (N + L) by RLVECT_1:def 3;

      then ((M + K) + ( 0. F)) = (L + N) by RLVECT_1: 5;

      then ((M + K) + ( - K)) = ((L + N) + ( - K)) by RLVECT_1: 4;

      then ((M + K) + ( - K)) = ((L + N) - K) by RLVECT_1:def 11;

      then (M + (K + ( - K))) = ((L + N) - K) by RLVECT_1:def 3;

      then (M + ( 0. F)) = ((L + N) - K) by RLVECT_1: 5;

      hence thesis by RLVECT_1: 4;

    end;

    theorem :: PARSP_2:5

    

     Th5: not (a,b) '||' (a,c) & (a,b) '||' (c,d) & (a,c) '||' (b,d) & [ [a, b], [c, d]] = [ [e, f], [g, h]] implies (h `1_3 ) = (((f `1_3 ) + (g `1_3 )) - (e `1_3 )) & (h `2_3 ) = (((f `2_3 ) + (g `2_3 )) - (e `2_3 )) & (h `3_3 ) = (((f `3_3 ) + (g `3_3 )) - (e `3_3 ))

    proof

      assume that

       A1: not (a,b) '||' (a,c) and

       A2: (a,b) '||' (c,d) and

       A3: (a,c) '||' (b,d) and

       A4: [ [a, b], [c, d]] = [ [e, f], [g, h]];

      consider m, n, o, w such that

       A6: [ [a, c], [b, d]] = [ [m, n], [o, w]] and

       A7: (ex L st (L * ((m `1_3 ) - (n `1_3 ))) = ((o `1_3 ) - (w `1_3 )) & (L * ((m `2_3 ) - (n `2_3 ))) = ((o `2_3 ) - (w `2_3 )) & (L * ((m `3_3 ) - (n `3_3 ))) = ((o `3_3 ) - (w `3_3 ))) or ((m `1_3 ) - (n `1_3 )) = ( 0. F) & ((m `2_3 ) - (n `2_3 )) = ( 0. F) & ((m `3_3 ) - (n `3_3 )) = ( 0. F) by A3, Th2;

      

       A8: b = f by A4, MCART_1: 93;

      then

       A9: o = f by A6, MCART_1: 93;

      d = h by A4, MCART_1: 93;

      then

       A10: w = h by A6, MCART_1: 93;

      c = g by A4, MCART_1: 93;

      then

       A11: n = g by A6, MCART_1: 93;

      

       A12: a = e by A4, MCART_1: 93;

      then

       A13: [ [a, b], [a, c]] = [ [e, f], [e, g]] by A4, A8, MCART_1: 93;

      consider i, j, k, l such that

       A14: [ [a, b], [c, d]] = [ [i, j], [k, l]] and

       A15: (ex K st (K * ((i `1_3 ) - (j `1_3 ))) = ((k `1_3 ) - (l `1_3 )) & (K * ((i `2_3 ) - (j `2_3 ))) = ((k `2_3 ) - (l `2_3 )) & (K * ((i `3_3 ) - (j `3_3 ))) = ((k `3_3 ) - (l `3_3 ))) or ((i `1_3 ) - (j `1_3 )) = ( 0. F) & ((i `2_3 ) - (j `2_3 )) = ( 0. F) & ((i `3_3 ) - (j `3_3 )) = ( 0. F) by A2, Th2;

      

       A16: e = i & f = j by A4, A14, MCART_1: 93;

      

       A17: g = k & h = l by A4, A14, MCART_1: 93;

      

       A18: e = m by A12, A6, MCART_1: 93;

      f = [(f `1_3 ), (f `2_3 ), (f `3_3 )];

      then (e `1_3 ) <> (f `1_3 ) or (e `2_3 ) <> (f `2_3 ) or (e `3_3 ) <> (f `3_3 ) by A1, A13, Th3;

      then

      consider K such that

       A19: (K * ((e `1_3 ) - (f `1_3 ))) = ((g `1_3 ) - (h `1_3 )) and

       A20: (K * ((e `2_3 ) - (f `2_3 ))) = ((g `2_3 ) - (h `2_3 )) and

       A21: (K * ((e `3_3 ) - (f `3_3 ))) = ((g `3_3 ) - (h `3_3 )) by A15, A16, A17, Lm2;

      g = [(g `1_3 ), (g `2_3 ), (g `3_3 )];

      then (e `1_3 ) <> (g `1_3 ) or (e `2_3 ) <> (g `2_3 ) or (e `3_3 ) <> (g `3_3 ) by A1, A13, Th3;

      then

      consider L such that

       A22: (L * ((e `1_3 ) - (g `1_3 ))) = ((f `1_3 ) - (h `1_3 )) and

       A23: (L * ((e `2_3 ) - (g `2_3 ))) = ((f `2_3 ) - (h `2_3 )) and

       A24: (L * ((e `3_3 ) - (g `3_3 ))) = ((f `3_3 ) - (h `3_3 )) by A7, A18, A11, A9, A10, Lm2;

      ((K * ((e `2_3 ) - (f `2_3 ))) - (L * ((e `2_3 ) - (g `2_3 )))) = ((g `2_3 ) - (f `2_3 )) by A20, A23, Lm5;

      then

       A25: ((K + ( - ( 1_ F))) * ((e `2_3 ) - (f `2_3 ))) = ((L + ( - ( 1_ F))) * ((e `2_3 ) - (g `2_3 ))) by Lm6;

      ((K * ((e `3_3 ) - (f `3_3 ))) - (L * ((e `3_3 ) - (g `3_3 )))) = ((g `3_3 ) - (f `3_3 )) by A21, A24, Lm5;

      then

       A26: ((K + ( - ( 1_ F))) * ((e `3_3 ) - (f `3_3 ))) = ((L + ( - ( 1_ F))) * ((e `3_3 ) - (g `3_3 ))) by Lm6;

      ((K * ((e `1_3 ) - (f `1_3 ))) - (L * ((e `1_3 ) - (g `1_3 )))) = ((g `1_3 ) - (f `1_3 )) by A19, A22, Lm5;

      then ((K + ( - ( 1_ F))) * ((e `1_3 ) - (f `1_3 ))) = ((L + ( - ( 1_ F))) * ((e `1_3 ) - (g `1_3 ))) by Lm6;

      then

       A27: (K + ( - ( 1_ F))) = ( 0. F) by A1, A13, A25, A26, Th4;

      then (((e `2_3 ) - (f `2_3 )) * ( 1_ F)) = ((g `2_3 ) - (h `2_3 )) by A20, Lm2;

      then

       A28: ((e `2_3 ) - (f `2_3 )) = ((g `2_3 ) - (h `2_3 ));

      (((e `3_3 ) - (f `3_3 )) * ( 1_ F)) = ((g `3_3 ) - (h `3_3 )) by A21, A27, Lm2;

      then

       A29: ((e `3_3 ) - (f `3_3 )) = ((g `3_3 ) - (h `3_3 ));

      (((e `1_3 ) - (f `1_3 )) * ( 1_ F)) = ((g `1_3 ) - (h `1_3 )) by A19, A27, Lm2;

      then ((e `1_3 ) - (f `1_3 )) = ((g `1_3 ) - (h `1_3 ));

      hence thesis by A28, A29, Lm7;

    end;

    

     Lm8: ((L * K) - (L * R)) = (R + K) implies ((L - ( 1_ F)) * K) = ((L + ( 1_ F)) * R)

    proof

      assume ((L * K) - (L * R)) = (R + K);

      

      then (((L * K) + ( - (L * R))) + ( - K)) = ((R + K) + ( - K)) by RLVECT_1:def 11

      .= (R + (K + ( - K))) by RLVECT_1:def 3

      .= (R + ( 0. F)) by RLVECT_1: 5

      .= R by RLVECT_1: 4;

      then (((L * K) + ( - K)) + ( - (L * R))) = R by RLVECT_1:def 3;

      then (((L * K) + ( - (( 1_ F) * K))) + ( - (L * R))) = R;

      then (((L * K) + (( - ( 1_ F)) * K)) + ( - (L * R))) = R by VECTSP_1: 9;

      then (((L + ( - ( 1_ F))) * K) + ( - (L * R))) = R by VECTSP_1:def 7;

      then ((((L - ( 1_ F)) * K) + ( - (L * R))) + (L * R)) = (R + (L * R)) by RLVECT_1:def 11;

      then (((L - ( 1_ F)) * K) + (( - (L * R)) + (L * R))) = (R + (L * R)) by RLVECT_1:def 3;

      then (((L - ( 1_ F)) * K) + ( 0. F)) = (R + (L * R)) by RLVECT_1: 5;

      

      then ((L - ( 1_ F)) * K) = ((L * R) + R) by RLVECT_1: 4

      .= ((L * R) + (( 1_ F) * R));

      hence thesis by VECTSP_1:def 7;

    end;

    

     Lm9: (L * (K - N)) = (R - S) & S = ((K + N) - R) implies ((L - ( 1_ F)) * (R - N)) = ((L + ( 1_ F)) * (R - K))

    proof

      assume (L * (K - N)) = (R - S) & S = ((K + N) - R);

      

      then

       A1: (L * (K - N)) = (R + ( - ((K + N) - R))) by RLVECT_1:def 11

      .= (R + (R + ( - (K + N)))) by RLVECT_1: 33

      .= (R + (R + (( - K) + ( - N)))) by RLVECT_1: 31

      .= (R + (( - N) + (R + ( - K)))) by RLVECT_1:def 3

      .= ((R + ( - N)) + (R + ( - K))) by RLVECT_1:def 3

      .= ((R - N) + (R + ( - K))) by RLVECT_1:def 11

      .= ((R - K) + (R - N)) by RLVECT_1:def 11;

      ((L * (R - N)) - (L * (R - K))) = ((L * (R + ( - N))) - (L * (R - K))) by RLVECT_1:def 11

      .= ((L * (R + ( - N))) - (L * (R + ( - K)))) by RLVECT_1:def 11

      .= ((L * (R + ( - N))) + ( - (L * (R + ( - K))))) by RLVECT_1:def 11

      .= (((L * R) + (L * ( - N))) + ( - (L * (R + ( - K))))) by VECTSP_1:def 7

      .= (((L * R) + (L * ( - N))) + (( - L) * (R + ( - K)))) by VECTSP_1: 9

      .= (((L * R) + (L * ( - N))) + ((( - L) * R) + (( - L) * ( - K)))) by VECTSP_1:def 7

      .= (((L * R) + (L * ( - N))) + ((( - L) * R) + (L * K))) by VECTSP_1: 10

      .= (((L * ( - N)) + (L * R)) + (( - (L * R)) + (L * K))) by VECTSP_1: 9

      .= ((((L * ( - N)) + (L * R)) + ( - (L * R))) + (L * K)) by RLVECT_1:def 3

      .= (((L * ( - N)) + ((L * R) + ( - (L * R)))) + (L * K)) by RLVECT_1:def 3

      .= (((L * ( - N)) + ( 0. F)) + (L * K)) by RLVECT_1: 5

      .= ((L * K) + (L * ( - N))) by RLVECT_1: 4

      .= (L * (K + ( - N))) by VECTSP_1:def 7

      .= (L * (K - N)) by RLVECT_1:def 11;

      hence thesis by A1, Lm8;

    end;

    

     Lm10: K = ((L + M) - N) & R = ((L + S) - N) implies (( 1_ F) * (M - S)) = (K - R)

    proof

      assume that

       A1: K = ((L + M) - N) and

       A2: R = ((L + S) - N);

      ( - R) = ( - ((L + S) + ( - N))) by A2, RLVECT_1:def 11

      .= (( - (L + S)) + ( - ( - N))) by RLVECT_1: 31

      .= (( - (L + S)) + N) by RLVECT_1: 17

      .= ((( - L) + ( - S)) + N) by RLVECT_1: 31;

      

      then (K - R) = (((L + M) - N) + ((( - L) + ( - S)) + N)) by A1, RLVECT_1:def 11

      .= (((M + L) + ( - N)) + ((( - L) + ( - S)) + N)) by RLVECT_1:def 11

      .= (((M + L) + ( - N)) + (( - S) + (( - L) + N))) by RLVECT_1:def 3

      .= ((M + (L + ( - N))) + (( - S) + (( - L) + N))) by RLVECT_1:def 3

      .= ((M + (L - N)) + (( - S) + (( - L) + N))) by RLVECT_1:def 11

      .= ((M + (L - N)) + (( - S) + (( - L) + ( - ( - N))))) by RLVECT_1: 17

      .= ((M + (L - N)) + (( - S) + ( - (L + ( - N))))) by RLVECT_1: 31

      .= ((M + (L - N)) + (( - (L - N)) + ( - S))) by RLVECT_1:def 11

      .= (((M + (L - N)) + ( - (L - N))) + ( - S)) by RLVECT_1:def 3

      .= ((M + ((L - N) + ( - (L - N)))) + ( - S)) by RLVECT_1:def 3

      .= ((M + ( 0. F)) + ( - S)) by RLVECT_1: 5

      .= (M + ( - S)) by RLVECT_1: 4

      .= ((M * ( 1_ F)) + ( - S))

      .= ((M * ( 1_ F)) + (( - S) * ( 1_ F)))

      .= ((M + ( - S)) * ( 1_ F))

      .= ((M - S) * ( 1_ F)) by RLVECT_1:def 11;

      hence thesis;

    end;

    theorem :: PARSP_2:6

    

     Th6: ex a, b, c st not (a,b) '||' (a,c)

    proof

      consider e,f,g be Element of [:the carrier of F, the carrier of F, the carrier of F:] such that

       A1: e = [( 1_ F), ( 1_ F), ( 0. F)] and

       A2: f = [( - ( 0. F)), ( 1_ F), ( 0. F)] and

       A3: g = [( 1_ F), ( - ( 0. F)), ( 0. F)];

      

       A4: (f `1_3 ) = ( - ( 0. F)) & (f `2_3 ) = ( 1_ F) by A2;

      

       A5: (g `1_3 ) = ( 1_ F) & (g `2_3 ) = ( - ( 0. F)) by A3;

      the carrier of ( MPS F) = [:the carrier of F, the carrier of F, the carrier of F:] by PARSP_1: 10;

      then

      consider a,b,c be Element of ( MPS F) such that

       A6: [ [a, b], [a, c]] = [ [e, f], [e, g]];

      take a, b, c;

      (e `1_3 ) = ( 1_ F) & (e `2_3 ) = ( 1_ F) by A1;

      

      then

       A7: ((((e `1_3 ) - (f `1_3 )) * ((e `2_3 ) - (g `2_3 ))) - (((e `1_3 ) - (g `1_3 )) * ((e `2_3 ) - (f `2_3 )))) = (((( 1. F) + ( - ( - ( 0. F)))) * (( 1. F) - ( - ( 0. F)))) - ((( 1. F) - ( 1. F)) * (( 1. F) - ( 1. F)))) by A4, A5, RLVECT_1:def 11

      .= (((( 1. F) + ( - ( - ( 0. F)))) * (( 1. F) + ( - ( - ( 0. F))))) - ((( 1. F) - ( 1. F)) * (( 1. F) - ( 1. F)))) by RLVECT_1:def 11

      .= (((( 1. F) + ( 0. F)) * (( 1. F) + ( - ( - ( 0. F))))) - ((( 1. F) - ( 1. F)) * (( 1. F) - ( 1. F)))) by RLVECT_1: 17

      .= (((( 1. F) + ( 0. F)) * (( 1. F) + ( 0. F))) - ((( 1. F) - ( 1. F)) * (( 1. F) - ( 1. F)))) by RLVECT_1: 17

      .= ((( 1. F) * (( 1. F) + ( 0. F))) - ((( 1. F) - ( 1. F)) * (( 1. F) - ( 1. F)))) by RLVECT_1: 4

      .= ((( 1. F) * ( 1. F)) - ((( 1. F) - ( 1. F)) * (( 1. F) - ( 1. F)))) by RLVECT_1: 4

      .= ((( 1. F) * ( 1. F)) - (( 0. F) * (( 1. F) - ( 1. F)))) by RLVECT_1: 15

      .= ((( 1. F) * ( 1. F)) - ( 0. F))

      .= (( 1. F) - ( 0. F));

      now

        let e9,f9,g9,h9 be Element of [:the carrier of F, the carrier of F, the carrier of F:];

        assume

         A8: [ [e9, f9], [g9, h9]] = [ [a, b], [a, c]];

        then

         A9: g9 = e & h9 = g by A6, MCART_1: 93;

        e9 = e & f9 = f by A6, A8, MCART_1: 93;

        hence ((((e9 `1_3 ) - (f9 `1_3 )) * ((g9 `2_3 ) - (h9 `2_3 ))) - (((g9 `1_3 ) - (h9 `1_3 )) * ((e9 `2_3 ) - (f9 `2_3 )))) <> ( 0. F) or ((((e9 `1_3 ) - (f9 `1_3 )) * ((g9 `3_3 ) - (h9 `3_3 ))) - (((g9 `1_3 ) - (h9 `1_3 )) * ((e9 `3_3 ) - (f9 `3_3 )))) <> ( 0. F) or ((((e9 `2_3 ) - (f9 `2_3 )) * ((g9 `3_3 ) - (h9 `3_3 ))) - (((g9 `2_3 ) - (h9 `2_3 )) * ((e9 `3_3 ) - (f9 `3_3 )))) <> ( 0. F) by A7, A9, Lm2;

      end;

      hence thesis by PARSP_1: 12;

    end;

    theorem :: PARSP_2:7

    

     Th7: (( 1_ F) + ( 1_ F)) <> ( 0. F) & (b,c) '||' (a,d) & (a,b) '||' (c,d) & (a,c) '||' (b,d) implies (a,b) '||' (a,c)

    proof

      assume that

       A1: (( 1_ F) + ( 1_ F)) <> ( 0. F) and

       A2: (b,c) '||' (a,d) and

       A3: (a,b) '||' (c,d) and

       A4: (a,c) '||' (b,d);

      assume

       A5: not thesis;

      consider i, j, k, l such that

       A6: [ [b, c], [a, d]] = [ [i, j], [k, l]] and

       A7: (ex L st (L * ((i `1_3 ) - (j `1_3 ))) = ((k `1_3 ) - (l `1_3 )) & (L * ((i `2_3 ) - (j `2_3 ))) = ((k `2_3 ) - (l `2_3 )) & (L * ((i `3_3 ) - (j `3_3 ))) = ((k `3_3 ) - (l `3_3 ))) or ((i `1_3 ) - (j `1_3 )) = ( 0. F) & ((i `2_3 ) - (j `2_3 )) = ( 0. F) & ((i `3_3 ) - (j `3_3 )) = ( 0. F) by A2, Th2;

      

       A8: b = i & c = j by A6, MCART_1: 93;

      

       A9: a = k & d = l by A6, MCART_1: 93;

      consider e, f, g, h such that

       A10: [ [a, b], [c, d]] = [ [e, f], [g, h]] and (ex K st (K * ((e `1_3 ) - (f `1_3 ))) = ((g `1_3 ) - (h `1_3 )) & (K * ((e `2_3 ) - (f `2_3 ))) = ((g `2_3 ) - (h `2_3 )) & (K * ((e `3_3 ) - (f `3_3 ))) = ((g `3_3 ) - (h `3_3 ))) or ((e `1_3 ) - (f `1_3 )) = ( 0. F) & ((e `2_3 ) - (f `2_3 )) = ( 0. F) & ((e `3_3 ) - (f `3_3 )) = ( 0. F) by A3, Th2;

      

       A11: b = f by A10, MCART_1: 93;

      

       A12: d = h by A10, MCART_1: 93;

      

       A13: c = g by A10, MCART_1: 93;

      

       A14: a = e by A10, MCART_1: 93;

      then

       A15: [ [a, b], [a, c]] = [ [e, f], [e, g]] by A10, A11, MCART_1: 93;

      f = [(f `1_3 ), (f `2_3 ), (f `3_3 )] & g = [(g `1_3 ), (g `2_3 ), (g `3_3 )];

      then (i `1_3 ) <> (j `1_3 ) or (i `2_3 ) <> (j `2_3 ) or (i `3_3 ) <> (j `3_3 ) by A5, A11, A13, A15, A8, Th3;

      then

      consider L such that

       A16: (L * ((f `1_3 ) - (g `1_3 ))) = ((e `1_3 ) - (h `1_3 )) and

       A17: (L * ((f `2_3 ) - (g `2_3 ))) = ((e `2_3 ) - (h `2_3 )) and

       A18: (L * ((f `3_3 ) - (g `3_3 ))) = ((e `3_3 ) - (h `3_3 )) by A14, A11, A13, A12, A7, A8, A9, Lm2;

      (h `2_3 ) = (((f `2_3 ) + (g `2_3 )) - (e `2_3 )) by A3, A4, A5, A10, Th5;

      then

       A19: ((L - ( 1_ F)) * ((e `2_3 ) - (g `2_3 ))) = ((L + ( 1_ F)) * ((e `2_3 ) - (f `2_3 ))) by A17, Lm9;

      (h `3_3 ) = (((f `3_3 ) + (g `3_3 )) - (e `3_3 )) by A3, A4, A5, A10, Th5;

      then

       A20: ((L - ( 1_ F)) * ((e `3_3 ) - (g `3_3 ))) = ((L + ( 1_ F)) * ((e `3_3 ) - (f `3_3 ))) by A18, Lm9;

      (h `1_3 ) = (((f `1_3 ) + (g `1_3 )) - (e `1_3 )) by A3, A4, A5, A10, Th5;

      then ((L - ( 1_ F)) * ((e `1_3 ) - (g `1_3 ))) = ((L + ( 1_ F)) * ((e `1_3 ) - (f `1_3 ))) by A16, Lm9;

      then (L + ( 1_ F)) = ( 0. F) & (L - ( 1_ F)) = ( 0. F) by A5, A15, A19, A20, Th4;

      then ((L + ( 1_ F)) - (L - ( 1_ F))) = (( 0. F) + ( - ( 0. F))) by RLVECT_1:def 11;

      then ((L + ( 1_ F)) - (L - ( 1_ F))) = ( 0. F) by RLVECT_1: 5;

      then ((L + ( 1_ F)) + ( - (L - ( 1_ F)))) = ( 0. F) by RLVECT_1:def 11;

      then ((L + ( 1_ F)) + (( 1_ F) + ( - L))) = ( 0. F) by RLVECT_1: 33;

      then (((L + ( 1_ F)) + ( 1_ F)) + ( - L)) = ( 0. F) by RLVECT_1:def 3;

      then (((( 1_ F) + ( 1_ F)) + L) + ( - L)) = ( 0. F) by RLVECT_1:def 3;

      then ((( 1_ F) + ( 1_ F)) + (L + ( - L))) = ( 0. F) by RLVECT_1:def 3;

      then ((( 1_ F) + ( 1_ F)) + ( 0. F)) = ( 0. F) by RLVECT_1: 5;

      hence contradiction by A1, RLVECT_1: 4;

    end;

    theorem :: PARSP_2:8

    

     Th8: not (a,p) '||' (a,b) & not (a,p) '||' (a,c) & (a,p) '||' (b,q) & (a,p) '||' (c,r) & (a,b) '||' (p,q) & (a,c) '||' (p,r) implies (b,c) '||' (q,r)

    proof

      assume that

       A1: not (a,p) '||' (a,b) and

       A2: not (a,p) '||' (a,c) and

       A3: (a,p) '||' (b,q) and

       A4: (a,p) '||' (c,r) and

       A5: (a,b) '||' (p,q) and

       A6: (a,c) '||' (p,r);

      consider i, j, k, l such that

       A7: [ [a, p], [c, r]] = [ [i, j], [k, l]] and (ex L st (L * ((i `1_3 ) - (j `1_3 ))) = ((k `1_3 ) - (l `1_3 )) & (L * ((i `2_3 ) - (j `2_3 ))) = ((k `2_3 ) - (l `2_3 )) & (L * ((i `3_3 ) - (j `3_3 ))) = ((k `3_3 ) - (l `3_3 ))) or ((i `1_3 ) - (j `1_3 )) = ( 0. F) & ((i `2_3 ) - (j `2_3 )) = ( 0. F) & ((i `3_3 ) - (j `3_3 )) = ( 0. F) by A4, Th2;

      consider e, f, g, h such that

       A8: [ [a, b], [p, q]] = [ [e, f], [g, h]] and (ex K st (K * ((e `1_3 ) - (f `1_3 ))) = ((g `1_3 ) - (h `1_3 )) & (K * ((e `2_3 ) - (f `2_3 ))) = ((g `2_3 ) - (h `2_3 )) & (K * ((e `3_3 ) - (f `3_3 ))) = ((g `3_3 ) - (h `3_3 ))) or ((e `1_3 ) - (f `1_3 )) = ( 0. F) & ((e `2_3 ) - (f `2_3 )) = ( 0. F) & ((e `3_3 ) - (f `3_3 )) = ( 0. F) by A5, Th2;

      

       A9: a = e & p = g by A8, MCART_1: 93;

      

       A10: c = k by A7, MCART_1: 93;

      then

       A11: [ [a, p], [c, r]] = [ [e, g], [k, l]] by A9, A7, MCART_1: 93;

      then

       A12: (l `1_3 ) = (((g `1_3 ) + (k `1_3 )) - (e `1_3 )) by A2, A4, A6, Th5;

      

       A13: b = f by A8, MCART_1: 93;

      then

       A14: [ [a, p], [b, q]] = [ [e, g], [f, h]] by A8, A9, MCART_1: 93;

      then (h `1_3 ) = (((g `1_3 ) + (f `1_3 )) - (e `1_3 )) by A1, A3, A5, Th5;

      then

       A15: (( 1_ F) * ((f `1_3 ) - (k `1_3 ))) = ((h `1_3 ) - (l `1_3 )) by A12, Lm10;

      

       A16: (l `3_3 ) = (((g `3_3 ) + (k `3_3 )) - (e `3_3 )) by A2, A4, A6, A11, Th5;

      

       A17: (l `2_3 ) = (((g `2_3 ) + (k `2_3 )) - (e `2_3 )) by A2, A4, A6, A11, Th5;

      (h `3_3 ) = (((g `3_3 ) + (f `3_3 )) - (e `3_3 )) by A1, A3, A5, A14, Th5;

      then

       A18: (( 1_ F) * ((f `3_3 ) - (k `3_3 ))) = ((h `3_3 ) - (l `3_3 )) by A16, Lm10;

      (h `2_3 ) = (((g `2_3 ) + (f `2_3 )) - (e `2_3 )) by A1, A3, A5, A14, Th5;

      then

       A19: (( 1_ F) * ((f `2_3 ) - (k `2_3 ))) = ((h `2_3 ) - (l `2_3 )) by A17, Lm10;

      q = h by A8, MCART_1: 93;

      then [ [b, c], [q, r]] = [ [f, k], [h, l]] by A13, A7, A10, MCART_1: 93;

      hence thesis by A15, A19, A18, Th2;

    end;

    definition

      let IT be ParSp;

      :: PARSP_2:def1

      attr IT is FanodesSp-like means

      : Def1: (ex a,b,c be Element of IT st not (a,b) '||' (a,c)) & (for a,b,c,d be Element of IT holds (b,c) '||' (a,d) & (a,b) '||' (c,d) & (a,c) '||' (b,d) implies (a,b) '||' (a,c)) & for a,b,c,p,q,r be Element of IT holds not (a,p) '||' (a,b) & not (a,p) '||' (a,c) & (a,p) '||' (b,q) & (a,p) '||' (c,r) & (a,b) '||' (p,q) & (a,c) '||' (p,r) implies (b,c) '||' (q,r);

    end

    registration

      cluster strict FanodesSp-like for ParSp;

      existence

      proof

        set FF = the Fanoian Field;

        reconsider FdSp = ( MPS FF) as ParSp by Th1;

        (( 1_ FF) + ( 1_ FF)) <> ( 0. FF) by VECTSP_1:def 19;

        then

         A1: for a,b,c,d be Element of FdSp holds (b,c) '||' (a,d) & (a,b) '||' (c,d) & (a,c) '||' (b,d) implies (a,b) '||' (a,c) by Th7;

        (ex a,b,c be Element of FdSp st not (a,b) '||' (a,c)) & for a,b,c,p,q,r be Element of FdSp holds not (a,p) '||' (a,b) & not (a,p) '||' (a,c) & (a,p) '||' (b,q) & (a,p) '||' (c,r) & (a,b) '||' (p,q) & (a,c) '||' (p,r) implies (b,c) '||' (q,r) by Th6, Th8;

        then FdSp is FanodesSp-like by A1;

        hence thesis;

      end;

    end

    definition

      mode FanodesSp is FanodesSp-like ParSp;

    end

    reserve FdSp for FanodesSp;

    reserve a,b,c,d,p,q,r,s,o,x,y for Element of FdSp;

    theorem :: PARSP_2:9

    

     Th9: p <> q implies ex r st not (p,q) '||' (p,r)

    proof

      consider a, b, c such that

       A1: not (a,b) '||' (a,c) by Def1;

      assume p <> q;

      then not (p,q) '||' (p,a) or not (p,q) '||' (p,b) or not (p,q) '||' (p,c) by A1, PARSP_1: 38;

      hence thesis;

    end;

    definition

      let FdSp, a, b, c;

      :: PARSP_2:def2

      pred a,b,c are_collinear means (a,b) '||' (a,c);

    end

    theorem :: PARSP_2:10

    

     Th10: (a,b,c) are_collinear implies (a,c,b) are_collinear & (c,b,a) are_collinear & (b,a,c) are_collinear & (b,c,a) are_collinear & (c,a,b) are_collinear by PARSP_1: 24;

    theorem :: PARSP_2:11

    

     Th11: not (a,b,c) are_collinear & (a,b) '||' (p,q) & (a,c) '||' (p,r) & p <> q & p <> r implies not (p,q,r) are_collinear by PARSP_1: 30;

    theorem :: PARSP_2:12

    

     Th12: a = b or b = c or c = a implies (a,b,c) are_collinear by PARSP_1: 25;

    theorem :: PARSP_2:13

    

     Th13: a <> b & (a,b,p) are_collinear & (a,b,q) are_collinear & (a,b,r) are_collinear implies (p,q,r) are_collinear

    proof

      assume that

       A1: a <> b and

       A2: (a,b,p) are_collinear and

       A3: (a,b,q) are_collinear and

       A4: (a,b,r) are_collinear ;

      

       A5: (a,b) '||' (a,p) by A2;

      (a,b) '||' (a,r) by A4;

      then

       A6: (a,b) '||' (p,r) by A5, PARSP_1: 35;

      (a,b) '||' (a,q) by A3;

      then (a,b) '||' (p,q) by A5, PARSP_1: 35;

      then (p,q) '||' (p,r) by A1, A6, PARSP_1:def 12;

      hence thesis;

    end;

    theorem :: PARSP_2:14

    

     Th14: p <> q implies ex r st not (p,q,r) are_collinear

    proof

      assume p <> q;

      then

      consider r such that

       A1: not (p,q) '||' (p,r) by Th9;

       not (p,q,r) are_collinear by A1;

      hence thesis;

    end;

    theorem :: PARSP_2:15

    

     Th15: (a,b,c) are_collinear & (a,b,d) are_collinear implies (a,b) '||' (c,d) by PARSP_1: 35;

    theorem :: PARSP_2:16

    

     Th16: not (a,b,c) are_collinear & (a,b) '||' (c,d) implies not (a,b,d) are_collinear

    proof

      assume that

       A1: not (a,b,c) are_collinear and

       A2: (a,b) '||' (c,d);

       A3:

      now

        assume that

         A4: c <> d and

         A5: a <> d;

        (a,c) '||' (c,a) & c <> a by A1, PARSP_1: 25;

        then not (c,d,a) are_collinear by A1, A2, A4, Th11;

        then

         A6: not (d,c,a) are_collinear by Th10;

        

         A7: (d,a) '||' (a,d) by PARSP_1: 25;

        a <> b & (d,c) '||' (a,b) by A1, A2, Th12, PARSP_1: 23;

        hence thesis by A5, A6, A7, Th11;

      end;

      a <> d by A1, A2, PARSP_1: 23;

      hence thesis by A1, A3;

    end;

    theorem :: PARSP_2:17

    

     Th17: not (a,b,c) are_collinear & (a,b) '||' (c,d) & c <> d implies not (a,b,x) are_collinear or not (c,d,x) are_collinear by Th16, PARSP_1: 26;

    theorem :: PARSP_2:18

     not (o,a,b) are_collinear implies not (o,a,x) are_collinear or not (o,b,x) are_collinear or o = x

    proof

      assume

       A1: not (o,a,b) are_collinear ;

      now

        assume that

         A2: (o,a,x) are_collinear and

         A3: (o,b,x) are_collinear ;

        (a,o,x) are_collinear by A2, Th10;

        then

         A4: (a,o) '||' (a,x);

        (b,o,x) are_collinear by A3, Th10;

        then

         A5: (b,o) '||' (b,x);

         not (a,b,o) are_collinear by A1, Th10;

        then not (a,b) '||' (a,o);

        hence thesis by A4, A5, PARSP_1: 33;

      end;

      hence thesis;

    end;

    theorem :: PARSP_2:19

    o <> a & o <> b & (o,a,b) are_collinear & (o,a,p) are_collinear & (o,b,q) are_collinear implies (a,b) '||' (p,q)

    proof

      assume that

       A1: o <> a and

       A2: o <> b and

       A3: (o,a,b) are_collinear and

       A4: (o,a,p) are_collinear and

       A5: (o,b,q) are_collinear ;

       A6:

      now

        

         A7: (o,a) '||' (o,b) by A3;

        (o,a) '||' (o,p) by A4;

        then

         A8: (o,b) '||' (o,p) by A1, A7, PARSP_1:def 12;

        (o,b) '||' (o,q) by A5;

        then (o,p) '||' (o,q) by A2, A8, PARSP_1:def 12;

        then

         A9: (o,p) '||' (p,q) by PARSP_1: 24;

        (o,b) '||' (a,b) by A7, PARSP_1: 24;

        then

         A10: (a,b) '||' (o,p) by A2, A8, PARSP_1:def 12;

        assume o <> p;

        hence thesis by A10, A9, PARSP_1: 26;

      end;

      now

        assume

         A11: o = p;

        then (p,a) '||' (p,b) by A3;

        then

         A12: (a,b) '||' (p,b) by PARSP_1: 24;

        (p,b) '||' (p,q) by A5, A11;

        hence thesis by A2, A11, A12, PARSP_1: 26;

      end;

      hence thesis by A6;

    end;

    theorem :: PARSP_2:20

     not (a,b) '||' (c,d) & (a,b,p) are_collinear & (a,b,q) are_collinear & (c,d,p) are_collinear & (c,d,q) are_collinear implies p = q

    proof

      assume that

       A1: not (a,b) '||' (c,d) and

       A2: (a,b,p) are_collinear & (a,b,q) are_collinear and

       A3: (c,d,p) are_collinear & (c,d,q) are_collinear ;

      (c,d) '||' (p,q) by A3, Th15;

      then

       A4: (p,q) '||' (c,d) by PARSP_1: 23;

      (a,b) '||' (p,q) by A2, Th15;

      then (p,q) '||' (a,b) by PARSP_1: 23;

      hence thesis by A1, A4, PARSP_1:def 12;

    end;

    theorem :: PARSP_2:21

    a <> b & (a,b,c) are_collinear & (a,b) '||' (c,d) implies (a,c) '||' (b,d)

    proof

      assume that

       A1: a <> b and

       A2: (a,b,c) are_collinear and

       A3: (a,b) '||' (c,d);

      now

        

         A4: (a,b) '||' (a,c) by A2;

        then (a,b) '||' (c,b) by PARSP_1: 24;

        then (c,b) '||' (c,d) by A1, A3, PARSP_1:def 12;

        then

         A5: (b,c) '||' (b,d) by PARSP_1: 24;

        assume

         A6: b <> c;

        (b,c) '||' (a,c) by A4, PARSP_1: 24;

        hence thesis by A6, A5, PARSP_1:def 12;

      end;

      hence thesis by A3;

    end;

    theorem :: PARSP_2:22

    a <> b & (a,b,c) are_collinear & (a,b) '||' (c,d) implies (c,b) '||' (c,d)

    proof

      assume that

       A1: a <> b and

       A2: (a,b,c) are_collinear and

       A3: (a,b) '||' (c,d);

      now

        (a,b) '||' (a,c) by A2;

        then

         A4: (a,c) '||' (c,b) & (a,c) '||' (c,d) by A1, A3, PARSP_1: 24, PARSP_1:def 12;

        assume a <> c;

        hence thesis by A4, PARSP_1:def 12;

      end;

      hence thesis by A3;

    end;

    theorem :: PARSP_2:23

     not (o,a,c) are_collinear & (o,a,b) are_collinear & (o,c,p) are_collinear & (o,c,q) are_collinear & (a,c) '||' (b,p) & (a,c) '||' (b,q) implies p = q by PARSP_1: 34;

    theorem :: PARSP_2:24

    a <> b & (a,b,c) are_collinear & (a,b,d) are_collinear implies (a,c,d) are_collinear by PARSP_1:def 12;

    theorem :: PARSP_2:25

    (a,b,c) are_collinear & (a,c,d) are_collinear & a <> c implies (b,c,d) are_collinear

    proof

      assume that

       A1: (a,b,c) are_collinear and

       A2: (a,c,d) are_collinear & a <> c;

      

       A3: (a,c,c) are_collinear by Th12;

      (a,c,b) are_collinear by A1, Th10;

      hence thesis by A2, A3, Th13;

    end;

    definition

      let FdSp, a, b, c, d;

      :: PARSP_2:def3

      pred parallelogram a,b,c,d means not (a,b,c) are_collinear & (a,b) '||' (c,d) & (a,c) '||' (b,d);

    end

    theorem :: PARSP_2:26

    

     Th26: parallelogram (a,b,c,d) implies a <> b & b <> c & c <> a & a <> d & b <> d & c <> d

    proof

      assume

       A1: parallelogram (a,b,c,d);

       A2:

      now

        assume a = d;

        then (a,b) '||' (c,a) by A1;

        then

         A3: (a,b) '||' (a,c) by PARSP_1: 23;

         not (a,b,c) are_collinear by A1;

        hence contradiction by A3;

      end;

       A4:

      now

        assume c = d;

        then (a,c) '||' (b,c) by A1;

        then (c,a) '||' (c,b) by PARSP_1: 23;

        then

         A5: (a,b) '||' (a,c) by PARSP_1: 24;

         not (a,b,c) are_collinear by A1;

        hence contradiction by A5;

      end;

       A6:

      now

        assume b = d;

        then (a,b) '||' (c,b) by A1;

        then (b,a) '||' (b,c) by PARSP_1: 23;

        then

         A7: (a,b) '||' (a,c) by PARSP_1: 24;

         not (a,b,c) are_collinear by A1;

        hence contradiction by A7;

      end;

       not (a,b,c) are_collinear by A1;

      hence thesis by A2, A6, A4, Th12;

    end;

    theorem :: PARSP_2:27

    

     Th27: parallelogram (a,b,c,d) implies not (a,b,c) are_collinear & not (b,a,d) are_collinear & not (c,d,a) are_collinear & not (d,c,b) are_collinear

    proof

      

       A1: (a,b) '||' (b,a) & (a,c) '||' (c,a) by PARSP_1: 25;

      assume

       A2: parallelogram (a,b,c,d);

      then

       A3: d <> b by Th26;

      (a,c) '||' (b,d) by A2;

      then

       A4: (a,c) '||' (d,b) by PARSP_1: 23;

      (a,b) '||' (c,d) by A2;

      then

       A5: (a,b) '||' (d,c) by PARSP_1: 23;

      

       A6: ( not (a,b,c) are_collinear ) & d <> c by A2, Th26;

      

       A7: (a,b) '||' (c,d) & c <> a by A2, Th26;

      (a,c) '||' (b,d) & b <> a by A2, Th26;

      hence thesis by A1, A7, A5, A4, A6, A3, Th11;

    end;

    theorem :: PARSP_2:28

    

     Th28: parallelogram (a,b,c,d) implies not (a,b,c) are_collinear & not (b,a,d) are_collinear & not (c,d,a) are_collinear & not (d,c,b) are_collinear & not (a,c,b) are_collinear & not (b,a,c) are_collinear & not (b,c,a) are_collinear & not (c,a,b) are_collinear & not (c,b,a) are_collinear & not (b,d,a) are_collinear & not (a,b,d) are_collinear & not (a,d,b) are_collinear & not (d,a,b) are_collinear & not (d,b,a) are_collinear & not (c,a,d) are_collinear & not (a,c,d) are_collinear & not (a,d,c) are_collinear & not (d,a,c) are_collinear & not (d,c,a) are_collinear & not (d,b,c) are_collinear & not (b,c,d) are_collinear & not (b,d,c) are_collinear & not (c,b,d) are_collinear & not (c,d,b) are_collinear

    proof

      assume

       A1: parallelogram (a,b,c,d);

      then

       A2: ( not (c,d,a) are_collinear ) & not (d,c,b) are_collinear by Th27;

      ( not (a,b,c) are_collinear ) & not (b,a,d) are_collinear by A1, Th27;

      hence thesis by A2, Th10;

    end;

    theorem :: PARSP_2:29

    

     Th29: parallelogram (a,b,c,d) implies not (a,b,x) are_collinear or not (c,d,x) are_collinear

    proof

      assume

       A1: parallelogram (a,b,c,d);

      then

       A2: c <> d by Th26;

      ( not (a,b,c) are_collinear ) & (a,b) '||' (c,d) by A1;

      hence thesis by A2, Th17;

    end;

    theorem :: PARSP_2:30

    

     Th30: parallelogram (a,b,c,d) implies parallelogram (a,c,b,d) by Th28;

    theorem :: PARSP_2:31

    

     Th31: parallelogram (a,b,c,d) implies parallelogram (c,d,a,b) by PARSP_1: 23, Th28;

    theorem :: PARSP_2:32

    

     Th32: parallelogram (a,b,c,d) implies parallelogram (b,a,d,c) by PARSP_1: 23, Th28;

    theorem :: PARSP_2:33

    

     Th33: parallelogram (a,b,c,d) implies parallelogram (a,c,b,d) & parallelogram (c,d,a,b) & parallelogram (b,a,d,c) & parallelogram (c,a,d,b) & parallelogram (d,b,c,a) & parallelogram (b,d,a,c) & parallelogram (d,c,b,a)

    proof

      assume

       A1: parallelogram (a,b,c,d);

      then parallelogram (c,d,a,b) by Th31;

      then

       A2: parallelogram (c,a,d,b) by Th30;

       parallelogram (b,a,d,c) by A1, Th32;

      hence thesis by A1, A2, Th30, Th31;

    end;

    theorem :: PARSP_2:34

    

     Th34: not (a,b,c) are_collinear implies ex d st parallelogram (a,b,c,d)

    proof

      consider d such that

       A1: (a,b) '||' (c,d) & (a,c) '||' (b,d) by PARSP_1:def 12;

      assume not (a,b,c) are_collinear ;

      then parallelogram (a,b,c,d) by A1;

      hence thesis;

    end;

    theorem :: PARSP_2:35

    

     Th35: parallelogram (a,b,c,p) & parallelogram (a,b,c,q) implies p = q

    proof

      assume that

       A1: parallelogram (a,b,c,p) and

       A2: parallelogram (a,b,c,q);

      (a,b) '||' (c,p) by A1;

      then

       A3: (b,c) '||' (c,b) & (b,a) '||' (c,p) by PARSP_1: 23, PARSP_1: 25;

      (a,b) '||' (c,q) by A2;

      then

       A4: (b,a) '||' (c,q) by PARSP_1: 23;

      (a,c) '||' (b,p) by A1;

      then

       A5: (c,a) '||' (b,p) by PARSP_1: 23;

      (a,c) '||' (b,q) by A2;

      then

       A6: (c,a) '||' (b,q) by PARSP_1: 23;

       not (b,c,a) are_collinear by A1, Th28;

      then not (b,c) '||' (b,a);

      hence thesis by A3, A4, A5, A6, PARSP_1: 34;

    end;

    theorem :: PARSP_2:36

    

     Th36: parallelogram (a,b,c,d) implies not (a,d) '||' (b,c)

    proof

      assume

       A1: parallelogram (a,b,c,d);

      then not (a,b,c) are_collinear ;

      then

       A2: not (a,b) '||' (a,c);

      (a,b) '||' (c,d) & (a,c) '||' (b,d) by A1;

      then not (b,c) '||' (a,d) by A2, Def1;

      hence thesis by PARSP_1: 19;

    end;

    theorem :: PARSP_2:37

    

     Th37: parallelogram (a,b,c,d) implies not parallelogram (a,b,d,c) by Th36;

    theorem :: PARSP_2:38

    

     Th38: a <> b implies ex c st (a,b,c) are_collinear & c <> a & c <> b

    proof

      assume a <> b;

      then

      consider p such that

       A1: not (a,b,p) are_collinear by Th14;

      consider q such that

       A2: parallelogram (a,b,p,q) by A1, Th34;

       not (p,q,b) are_collinear by A2, Th28;

      then

      consider c such that

       A3: parallelogram (p,q,b,c) by Th34;

      

       A4: (p,q) '||' (b,c) by A3;

      p <> q & (a,b) '||' (p,q) by A2, Th26;

      then (a,b) '||' (b,c) by A4, PARSP_1: 26;

      then (b,a) '||' (b,c) by PARSP_1: 23;

      then (b,a,c) are_collinear ;

      then

       A5: (a,b,c) are_collinear by Th10;

      

       A6: not (a,q) '||' (b,p) by A2, Th36;

      (p,b) '||' (q,c) by A3;

      then

       A7: a <> c by A6, PARSP_1: 23;

      b <> c by A3, Th26;

      hence thesis by A7, A5;

    end;

    theorem :: PARSP_2:39

    

     Th39: parallelogram (a,p,b,q) & parallelogram (a,p,c,r) implies (b,c) '||' (q,r)

    proof

      assume that

       A1: parallelogram (a,p,b,q) and

       A2: parallelogram (a,p,c,r);

      

       A3: (a,p) '||' (c,r) & (a,c) '||' (p,r) by A2;

       not (a,p,c) are_collinear by A2;

      then

       A4: not (a,p) '||' (a,c);

       not (a,p,b) are_collinear by A1;

      then

       A5: not (a,p) '||' (a,b);

      (a,p) '||' (b,q) & (a,b) '||' (p,q) by A1;

      hence thesis by A5, A4, A3, Def1;

    end;

    theorem :: PARSP_2:40

    

     Th40: not (b,q,c) are_collinear & parallelogram (a,p,b,q) & parallelogram (a,p,c,r) implies parallelogram (b,q,c,r)

    proof

      assume that

       A1: not (b,q,c) are_collinear and

       A2: parallelogram (a,p,b,q) and

       A3: parallelogram (a,p,c,r);

      

       A4: (a,p) '||' (c,r) by A3;

      a <> p & (a,p) '||' (b,q) by A2, Th26;

      then

       A5: (b,q) '||' (c,r) by A4, PARSP_1:def 12;

      (b,c) '||' (q,r) by A2, A3, Th39;

      hence thesis by A1, A5;

    end;

    theorem :: PARSP_2:41

    

     Th41: (a,b,c) are_collinear & b <> c & parallelogram (a,p,b,q) & parallelogram (a,p,c,r) implies parallelogram (b,q,c,r)

    proof

      assume that

       A1: (a,b,c) are_collinear and

       A2: b <> c and

       A3: parallelogram (a,p,b,q) and

       A4: parallelogram (a,p,c,r);

      

       A5: b <> q by A3, Th26;

      (a,b) '||' (a,c) by A1;

      then

       A6: (a,b) '||' (b,c) by PARSP_1: 24;

      thus thesis by A2, A3, A4, A5, A6, Th11, Th40;

    end;

    theorem :: PARSP_2:42

    

     Th42: parallelogram (a,p,b,q) & parallelogram (a,p,c,r) & parallelogram (b,q,d,s) implies (c,d) '||' (r,s)

    proof

      assume that

       A1: parallelogram (a,p,b,q) and

       A2: parallelogram (a,p,c,r) and

       A3: parallelogram (b,q,d,s);

       A4:

      now

        assume

         A5: not (a,p,d) are_collinear ;

         parallelogram (b,q,a,p) by A1, Th33;

        then parallelogram (a,p,d,s) by A3, A5, Th40;

        hence thesis by A2, Th39;

      end;

       A6:

      now

        

         A7: a <> p by A1, Th26;

        

         A8: ( not (a,p,b) are_collinear ) & (a,p) '||' (a,p) by A1, PARSP_1: 25;

        assume that

         A9: (b,q,c) are_collinear and

         A10: (a,p,d) are_collinear ;

        a <> b by A1, Th26;

        then

        consider x such that

         A11: (a,b,x) are_collinear and

         A12: x <> a and

         A13: x <> b by Th38;

        (a,b) '||' (a,x) by A11;

        then

        consider y such that

         A14: parallelogram (a,p,x,y) by A12, A8, A7, Th11, Th34;

        

         A15: not (x,y,d) are_collinear by A10, A14, Th29;

         parallelogram (b,q,x,y) by A1, A11, A13, A14, Th41;

        then

         A16: parallelogram (x,y,d,s) by A3, A15, Th40;

         not (x,y,c) are_collinear by A1, A9, A11, A13, A14, Th29, Th41;

        then parallelogram (x,y,c,r) by A2, A14, Th40;

        hence thesis by A16, Th39;

      end;

      now

        assume not (b,q,c) are_collinear ;

        then parallelogram (b,q,c,r) by A1, A2, Th40;

        hence thesis by A3, Th39;

      end;

      hence thesis by A4, A6;

    end;

    theorem :: PARSP_2:43

    

     Th43: a <> b implies ex c, d st parallelogram (a,b,c,d)

    proof

      assume a <> b;

      then

      consider c such that

       A1: not (a,b,c) are_collinear by Th14;

      ex d st parallelogram (a,b,c,d) by A1, Th34;

      hence thesis;

    end;

    theorem :: PARSP_2:44

    a <> d implies ex b, c st parallelogram (a,b,c,d)

    proof

      assume a <> d;

      then

      consider b such that

       A1: not (a,d,b) are_collinear by Th14;

       not (b,a,d) are_collinear by A1, Th10;

      then

      consider c such that

       A2: parallelogram (b,a,d,c) by Th34;

       parallelogram (a,b,c,d) by A2, Th33;

      hence thesis;

    end;

    definition

      let FdSp, a, b, r, s;

      :: PARSP_2:def4

      pred a,b congr r,s means a = b & r = s or ex p, q st parallelogram (p,q,a,b) & parallelogram (p,q,r,s);

    end

    theorem :: PARSP_2:45

    

     Th45: (a,a) congr (b,c) implies b = c by Th26;

    theorem :: PARSP_2:46

    (a,b) congr (c,c) implies a = b by Th26;

    theorem :: PARSP_2:47

    (a,b) congr (b,a) implies a = b by Th37;

    theorem :: PARSP_2:48

    

     Th48: (a,b) congr (c,d) implies (a,b) '||' (c,d)

    proof

      assume

       A1: (a,b) congr (c,d);

      now

        assume a <> b;

        then

        consider p, q such that

         A2: parallelogram (p,q,a,b) and

         A3: parallelogram (p,q,c,d) by A1;

        

         A4: (p,q) '||' (c,d) by A3;

        p <> q & (p,q) '||' (a,b) by A2, Th26;

        hence thesis by A4, PARSP_1:def 12;

      end;

      hence thesis by PARSP_1: 20;

    end;

    theorem :: PARSP_2:49

    

     Th49: (a,b) congr (c,d) implies (a,c) '||' (b,d)

    proof

      assume

       A1: (a,b) congr (c,d);

       A2:

      now

        assume

         A3: a = b;

        then c = d by A1, Th45;

        hence thesis by A3, PARSP_1: 25;

      end;

      a <> b implies thesis by A1, Th39;

      hence thesis by A2;

    end;

    theorem :: PARSP_2:50

    

     Th50: (a,b) congr (c,d) & not (a,b,c) are_collinear implies parallelogram (a,b,c,d) by Th48, Th49;

    theorem :: PARSP_2:51

    

     Th51: parallelogram (a,b,c,d) implies (a,b) congr (c,d)

    proof

      

       A1: (a,b) '||' (a,b) by PARSP_1: 25;

      assume

       A2: parallelogram (a,b,c,d);

      then

       A3: ( not (a,c,b) are_collinear ) & a <> b by Th26, Th28;

      a <> c by A2, Th26;

      then

      consider p such that

       A4: (a,c,p) are_collinear and

       A5: a <> p and

       A6: c <> p by Th38;

      (a,c) '||' (a,p) by A4;

      then

      consider q such that

       A7: parallelogram (a,p,b,q) by A5, A1, A3, Th11, Th34;

       parallelogram (a,b,p,q) by A7, Th33;

      then parallelogram (c,d,p,q) by A2, A4, A6, Th41;

      then

       A8: parallelogram (p,q,c,d) by Th33;

       parallelogram (p,q,a,b) by A7, Th33;

      hence thesis by A8;

    end;

    theorem :: PARSP_2:52

    

     Th52: (a,b) congr (c,d) & (a,b,c) are_collinear & parallelogram (r,s,a,b) implies parallelogram (r,s,c,d)

    proof

      assume that

       A1: (a,b) congr (c,d) and

       A2: (a,b,c) are_collinear and

       A3: parallelogram (r,s,a,b);

      now

        assume

         A4: a <> b;

        then

        consider p, q such that

         A5: parallelogram (p,q,a,b) and

         A6: parallelogram (p,q,c,d) by A1;

        (r,s) '||' (a,b) & (a,b) '||' (c,d) by A1, A3, Th48;

        then

         A7: (r,s) '||' (c,d) by A4, PARSP_1: 26;

        

         A8: parallelogram (a,b,r,s) by A3, Th33;

         parallelogram (a,b,p,q) by A5, Th33;

        then

         A9: (r,c) '||' (s,d) by A6, A8, Th42;

         not (r,s,c) are_collinear by A2, A3, Th29;

        hence thesis by A7, A9;

      end;

      hence thesis by A3, Th26;

    end;

    theorem :: PARSP_2:53

    (a,b) congr (c,x) & (a,b) congr (c,y) implies x = y

    proof

      assume that

       A1: (a,b) congr (c,x) and

       A2: (a,b) congr (c,y);

       A3:

      now

        assume that a <> b and

         A4: not (a,b,c) are_collinear ;

         parallelogram (a,b,c,x) & parallelogram (a,b,c,y) by A1, A2, A4, Th50;

        hence thesis by Th35;

      end;

       A5:

      now

        assume that

         A6: a <> b and

         A7: (a,b,c) are_collinear ;

        consider p, q such that

         A8: parallelogram (a,b,p,q) by A6, Th43;

         parallelogram (p,q,a,b) by A8, Th33;

        then parallelogram (p,q,c,x) & parallelogram (p,q,c,y) by A1, A2, A7, Th52;

        hence thesis by Th35;

      end;

      now

        assume

         A9: a = b;

        then c = x by A1, Th45;

        hence thesis by A2, A9, Th45;

      end;

      hence thesis by A5, A3;

    end;

    theorem :: PARSP_2:54

    ex d st (a,b) congr (c,d)

    proof

       A1:

      now

        assume a = b;

        then (a,b) congr (c,c);

        hence thesis;

      end;

       A2:

      now

        assume that

         A3: a <> b and

         A4: (a,b,c) are_collinear ;

        consider p, q such that

         A5: parallelogram (a,b,p,q) by A3, Th43;

         not (p,q,c) are_collinear by A4, A5, Th29;

        then

        consider d such that

         A6: parallelogram (p,q,c,d) by Th34;

         parallelogram (p,q,a,b) by A5, Th33;

        then (a,b) congr (c,d) by A6;

        hence thesis;

      end;

      now

        assume that a <> b and

         A7: not (a,b,c) are_collinear ;

        ex d st parallelogram (a,b,c,d) by A7, Th34;

        hence thesis by Th51;

      end;

      hence thesis by A1, A2;

    end;

    theorem :: PARSP_2:55

    (a,b) congr (a,b)

    proof

      now

        assume a <> b;

        then

        consider p, q such that

         A1: parallelogram (a,b,p,q) by Th43;

         parallelogram (p,q,a,b) by A1, Th33;

        hence thesis;

      end;

      hence thesis;

    end;

    theorem :: PARSP_2:56

    (r,s) congr (a,b) & (r,s) congr (c,d) implies (a,b) congr (c,d)

    proof

      assume that

       A1: (r,s) congr (a,b) and

       A2: (r,s) congr (c,d);

       A3:

      now

        assume that r <> s and

         A4: ( not (r,s,a) are_collinear ) & not (r,s,c) are_collinear ;

         parallelogram (r,s,a,b) & parallelogram (r,s,c,d) by A1, A2, A4, Th50;

        hence thesis;

      end;

       A5:

      now

        assume that

         A6: r <> s and

         A7: (r,s,c) are_collinear ;

        consider p, q such that

         A8: parallelogram (p,q,r,s) and

         A9: parallelogram (p,q,a,b) by A1, A6;

         parallelogram (p,q,c,d) by A2, A7, A8, Th52;

        hence thesis by A9;

      end;

       A10:

      now

        assume that

         A11: r <> s and

         A12: (r,s,a) are_collinear ;

        consider p, q such that

         A13: parallelogram (p,q,r,s) and

         A14: parallelogram (p,q,c,d) by A2, A11;

         parallelogram (p,q,a,b) by A1, A12, A13, Th52;

        hence thesis by A14;

      end;

      r = s implies thesis by A1, A2, Th45;

      hence thesis by A10, A5, A3;

    end;

    theorem :: PARSP_2:57

    (a,b) congr (c,d) implies (c,d) congr (a,b);

    theorem :: PARSP_2:58

    (a,b) congr (c,d) implies (b,a) congr (d,c)

    proof

      assume

       A1: (a,b) congr (c,d);

       A2:

      now

        assume a <> b;

        then

        consider p, q such that

         A3: parallelogram (p,q,a,b) & parallelogram (p,q,c,d) by A1;

         parallelogram (q,p,b,a) & parallelogram (q,p,d,c) by A3, Th33;

        hence thesis;

      end;

      a = b implies thesis by A1, Th45;

      hence thesis by A2;

    end;