let X be non empty set ; :: thesis: for Y being ComplexNormSpace
for f, g, h being VECTOR of
for f', g', h' being bounded Function of X,the carrier of Y st f' = f & g' = g & h' = h holds
( h = f + g iff for x being Element of X holds h' . x = (f' . x) + (g' . x) )
let Y be ComplexNormSpace; :: thesis: for f, g, h being VECTOR of
for f', g', h' being bounded Function of X,the carrier of Y st f' = f & g' = g & h' = h holds
( h = f + g iff for x being Element of X holds h' . x = (f' . x) + (g' . x) )
let f, g, h be VECTOR of ; :: thesis: for f', g', h' being bounded Function of X,the carrier of Y st f' = f & g' = g & h' = h holds
( h = f + g iff for x being Element of X holds h' . x = (f' . x) + (g' . x) )
A1: C_VectorSpace_of_BoundedFunctions X,Y is Subspace of ComplexVectSpace X,Y by Th8, CSSPACE:13;
then reconsider f1 = f as VECTOR of by CLVECT_1:30;
reconsider h1 = h as VECTOR of by A1, CLVECT_1:30;
reconsider g1 = g as VECTOR of by A1, CLVECT_1:30;
let f', g', h' be bounded Function of X,the carrier of Y; :: thesis: ( f' = f & g' = g & h' = h implies ( h = f + g iff for x being Element of X holds h' . x = (f' . x) + (g' . x) ) )
assume A2: ( f' = f & g' = g & h' = h ) ; :: thesis: ( h = f + g iff for x being Element of X holds h' . x = (f' . x) + (g' . x) )

A3: now

assume A4: h = f + g ; :: thesis: for x being Element of X holds h' . x = (f' . x) + (g' . x)
let x be Element of X; :: thesis: h' . x = (f' . x) + (g' . x)
h1 = f1 + g1 by A1, A4, CLVECT_1:33;
hence h' . x = (f' . x) + (g' . x) by A2, CLOPBAN1:12; :: thesis: verum

end;

now

assume for x being Element of X holds h' . x = (f' . x) + (g' . x) ; :: thesis: h = f + g
then h1 = f1 + g1 by A2, CLOPBAN1:12;
hence h = f + g by A1, CLVECT_1:33; :: thesis: verum

end;

hence ( h = f + g iff for x being Element of X holds h' . x = (f' . x) + (g' . x) ) by A3; :: thesis: verum