let C be non empty set ; :: thesis: for f1, f, g1, g being PartFunc of C,COMPLEX holds (f1 / f) + (g1 / g) = ((f1 (#) g) + (g1 (#) f)) / (f (#) g)
let f1, f, g1, g be PartFunc of C,COMPLEX ; :: thesis: (f1 / f) + (g1 / g) = ((f1 (#) g) + (g1 (#) f)) / (f (#) g)
A1: now
let c be Element of C; :: thesis: ( c in dom ((f1 / f) + (g1 / g)) implies ((f1 / f) + (g1 / g)) /. c = (((f1 (#) g) + (g1 (#) f)) / (f (#) g)) /. c )
A2: dom (f ^ ) c= dom f by Th15;
assume A3: c in dom ((f1 / f) + (g1 / g)) ; :: thesis: ((f1 / f) + (g1 / g)) /. c = (((f1 (#) g) + (g1 (#) f)) / (f (#) g)) /. c
then A4: c in (dom (f1 / f)) /\ (dom (g1 / g)) by VALUED_1:def 1;
then A5: c in dom (f1 / f) by XBOOLE_0:def 4;
A6: c in dom (g1 / g) by A4, XBOOLE_0:def 4;
A7: c in (dom (f1 (#) (f ^ ))) /\ (dom (g1 / g)) by A4, Th51;
then c in dom (f1 (#) (f ^ )) by XBOOLE_0:def 4;
then A8: c in (dom f1) /\ (dom (f ^ )) by Th5;
then A9: c in dom (f ^ ) by XBOOLE_0:def 4;
then A10: f /. c <> 0c by Th17;
c in (dom (f1 (#) (f ^ ))) /\ (dom (g1 (#) (g ^ ))) by A7, Th51;
then c in dom (g1 (#) (g ^ )) by XBOOLE_0:def 4;
then A11: c in (dom g1) /\ (dom (g ^ )) by Th5;
then A12: c in dom (g ^ ) by XBOOLE_0:def 4;
then A13: g /. c <> 0c by Th17;
c in dom g1 by A11, XBOOLE_0:def 4;
then c in (dom g1) /\ (dom f) by A9, A2, XBOOLE_0:def 4;
then A14: c in dom (g1 (#) f) by Th5;
A15: dom (g ^ ) c= dom g by Th15;
then c in (dom f) /\ (dom g) by A9, A12, A2, XBOOLE_0:def 4;
then A16: c in dom (f (#) g) by Th5;
c in dom f1 by A8, XBOOLE_0:def 4;
then c in (dom f1) /\ (dom g) by A12, A15, XBOOLE_0:def 4;
then A17: c in dom (f1 (#) g) by Th5;
then c in (dom (f1 (#) g)) /\ (dom (g1 (#) f)) by A14, XBOOLE_0:def 4;
then A18: c in dom ((f1 (#) g) + (g1 (#) f)) by VALUED_1:def 1;
c in (dom (f ^ )) /\ (dom (g ^ )) by A9, A12, XBOOLE_0:def 4;
then c in dom ((f ^ ) (#) (g ^ )) by Th5;
then c in dom ((f (#) g) ^ ) by Th45;
then c in (dom ((f1 (#) g) + (g1 (#) f))) /\ (dom ((f (#) g) ^ )) by A18, XBOOLE_0:def 4;
then c in dom (((f1 (#) g) + (g1 (#) f)) (#) ((f (#) g) ^ )) by Th5;
then A19: c in dom (((f1 (#) g) + (g1 (#) f)) / (f (#) g)) by Th51;
thus ((f1 / f) + (g1 / g)) /. c = ((f1 / f) /. c) + ((g1 / g) /. c) by A3, Th3
.= ((f1 /. c) * ((f /. c) " )) + ((g1 / g) /. c) by A5, Def1
.= ((f1 /. c) * (1r * ((f /. c) " ))) + (((g1 /. c) * 1r ) * ((g /. c) " )) by A6, Def1, COMPLEX1:def 7
.= ((f1 /. c) * (((g /. c) * ((g /. c) " )) * ((f /. c) " ))) + ((g1 /. c) * (1r * ((g /. c) " ))) by A13, COMPLEX1:def 7, XCMPLX_0:def 7
.= ((f1 /. c) * ((g /. c) * (((g /. c) " ) * ((f /. c) " )))) + ((g1 /. c) * (((f /. c) * ((f /. c) " )) * ((g /. c) " ))) by A10, COMPLEX1:def 7, XCMPLX_0:def 7
.= ((f1 /. c) * ((g /. c) * (((g /. c) * (f /. c)) " ))) + ((g1 /. c) * ((f /. c) * (((f /. c) " ) * ((g /. c) " )))) by XCMPLX_1:205
.= ((f1 /. c) * ((g /. c) * (((f /. c) * (g /. c)) " ))) + ((g1 /. c) * ((f /. c) * (((f /. c) * (g /. c)) " ))) by XCMPLX_1:205
.= ((f1 /. c) * ((g /. c) * (((f (#) g) /. c) " ))) + ((g1 /. c) * ((f /. c) * (((f /. c) * (g /. c)) " ))) by A16, Th5
.= (((f1 /. c) * (g /. c)) * (((f (#) g) /. c) " )) + ((g1 /. c) * ((f /. c) * (((f (#) g) /. c) " ))) by A16, Th5
.= (((f1 (#) g) /. c) * (((f (#) g) /. c) " )) + (((g1 /. c) * (f /. c)) * (((f (#) g) /. c) " )) by A17, Th5
.= (((f1 (#) g) /. c) * (((f (#) g) /. c) " )) + (((g1 (#) f) /. c) * (((f (#) g) /. c) " )) by A14, Th5
.= (((f1 (#) g) /. c) + ((g1 (#) f) /. c)) * (((f (#) g) /. c) " )
.= (((f1 (#) g) + (g1 (#) f)) /. c) * (((f (#) g) /. c) " ) by A18, Th3
.= (((f1 (#) g) + (g1 (#) f)) / (f (#) g)) /. c by A19, Def1 ; :: thesis: verum
end;
dom ((f1 / f) + (g1 / g)) = (dom (f1 / f)) /\ (dom (g1 / g)) by VALUED_1:def 1
.= ((dom f1) /\ ((dom f) \ (f " {0c }))) /\ (dom (g1 / g)) by Def1
.= ((dom f1) /\ ((dom f) \ (f " {0c }))) /\ ((dom g1) /\ ((dom g) \ (g " {0c }))) by Def1
.= ((dom f1) /\ ((dom f) /\ ((dom f) \ (f " {0c })))) /\ ((dom g1) /\ ((dom g) \ (g " {0c }))) by Th15
.= (((dom f) /\ ((dom f) \ (f " {0c }))) /\ (dom f1)) /\ (((dom g) /\ ((dom g) \ (g " {0c }))) /\ (dom g1)) by Th15
.= ((dom f) /\ ((dom f) \ (f " {0c }))) /\ ((dom f1) /\ (((dom g) /\ ((dom g) \ (g " {0c }))) /\ (dom g1))) by XBOOLE_1:16
.= ((dom f) /\ ((dom f) \ (f " {0c }))) /\ (((dom f1) /\ ((dom g) /\ ((dom g) \ (g " {0c })))) /\ (dom g1)) by XBOOLE_1:16
.= ((dom f) /\ ((dom f) \ (f " {0c }))) /\ ((((dom f1) /\ (dom g)) /\ ((dom g) \ (g " {0c }))) /\ (dom g1)) by XBOOLE_1:16
.= ((dom f) /\ ((dom f) \ (f " {0c }))) /\ (((dom (f1 (#) g)) /\ ((dom g) \ (g " {0c }))) /\ (dom g1)) by Th5
.= ((dom f) /\ ((dom f) \ (f " {0c }))) /\ ((dom (f1 (#) g)) /\ ((dom g1) /\ ((dom g) \ (g " {0c })))) by XBOOLE_1:16
.= (dom (f1 (#) g)) /\ ((((dom f) \ (f " {0c })) /\ (dom f)) /\ ((dom g1) /\ ((dom g) \ (g " {0c })))) by XBOOLE_1:16
.= (dom (f1 (#) g)) /\ (((dom f) \ (f " {0c })) /\ ((dom f) /\ ((dom g1) /\ ((dom g) \ (g " {0c }))))) by XBOOLE_1:16
.= (dom (f1 (#) g)) /\ (((dom f) \ (f " {0c })) /\ (((dom g1) /\ (dom f)) /\ ((dom g) \ (g " {0c })))) by XBOOLE_1:16
.= (dom (f1 (#) g)) /\ (((dom f) \ (f " {0c })) /\ ((dom (g1 (#) f)) /\ ((dom g) \ (g " {0c })))) by Th5
.= (dom (f1 (#) g)) /\ ((dom (g1 (#) f)) /\ (((dom f) \ (f " {0c })) /\ ((dom g) \ (g " {0c })))) by XBOOLE_1:16
.= ((dom (f1 (#) g)) /\ (dom (g1 (#) f))) /\ (((dom f) \ (f " {0c })) /\ ((dom g) \ (g " {0c }))) by XBOOLE_1:16
.= (dom ((f1 (#) g) + (g1 (#) f))) /\ (((dom f) \ (f " {0c })) /\ ((dom g) \ (g " {0c }))) by VALUED_1:def 1
.= (dom ((f1 (#) g) + (g1 (#) f))) /\ ((dom (f (#) g)) \ ((f (#) g) " {0c })) by Th16
.= dom (((f1 (#) g) + (g1 (#) f)) / (f (#) g)) by Def1 ;
hence (f1 / f) + (g1 / g) = ((f1 (#) g) + (g1 (#) f)) / (f (#) g) by A1, PARTFUN2:3; :: thesis: verum