let X be non empty set ; for S being SigmaField of X
for M being sigma_Measure of S
for f, g being PartFunc of X,COMPLEX
for v, u being VECTOR of (CLSp_L1Funct M) st f = v & g = u holds
f + g = v + u
let S be SigmaField of X; for M being sigma_Measure of S
for f, g being PartFunc of X,COMPLEX
for v, u being VECTOR of (CLSp_L1Funct M) st f = v & g = u holds
f + g = v + u
let M be sigma_Measure of S; for f, g being PartFunc of X,COMPLEX
for v, u being VECTOR of (CLSp_L1Funct M) st f = v & g = u holds
f + g = v + u
let f, g be PartFunc of X,COMPLEX; for v, u being VECTOR of (CLSp_L1Funct M) st f = v & g = u holds
f + g = v + u
let v, u be VECTOR of (CLSp_L1Funct M); ( f = v & g = u implies f + g = v + u )
reconsider v2 = v, u2 = u as VECTOR of (CLSp_PFunct X) by TARSKI:def 3;
reconsider h = v2 + u2 as Element of PFuncs (X,COMPLEX) ;
reconsider v3 = v2, u3 = u2 as Element of PFuncs (X,COMPLEX) ;
A1:
dom h = (dom v3) /\ (dom u3)
by Th4;
assume A2:
( f = v & g = u )
; f + g = v + u
then
for x being object st x in dom h holds
h . x = (f . x) + (g . x)
by Th4;
then
h = f + g
by A2, A1, VALUED_1:def 1;
hence
f + g = v + u
by ZFMISC_1:87, FUNCT_1:49; verum