let V be non empty CLSStruct ; for L1, L2 being C_Linear_Combination of V holds (vector ((LC_CLSpace V),L1)) - (vector ((LC_CLSpace V),L2)) = L1 - L2
let L1, L2 be C_Linear_Combination of V; (vector ((LC_CLSpace V),L1)) - (vector ((LC_CLSpace V),L2)) = L1 - L2
- L2 in C_LinComb V
by Def12;
then A1:
- L2 in LC_CLSpace V
;
- (vector ((LC_CLSpace V),L2)) =
- L2
by Th40
.=
vector ((LC_CLSpace V),(- L2))
by A1, RLVECT_2:def 1
;
hence
(vector ((LC_CLSpace V),L1)) - (vector ((LC_CLSpace V),L2)) = L1 - L2
by Th38; verum