let RNS1, RNS2 be RealLinearSpace; ( RLSStruct(# the carrier of RNS1, the ZeroF of RNS1, the addF of RNS1, the Mult of RNS1 #) = RLSStruct(# the carrier of RNS2, the ZeroF of RNS2, the addF of RNS2, the Mult of RNS2 #) implies for L being Linear_Combination of RNS2
for S being Linear_Combination of RNS1 st L = S holds
Sum L = Sum S )
assume A1:
RLSStruct(# the carrier of RNS1, the ZeroF of RNS1, the addF of RNS1, the Mult of RNS1 #) = RLSStruct(# the carrier of RNS2, the ZeroF of RNS2, the addF of RNS2, the Mult of RNS2 #)
; for L being Linear_Combination of RNS2
for S being Linear_Combination of RNS1 st L = S holds
Sum L = Sum S
let L be Linear_Combination of RNS2; for S being Linear_Combination of RNS1 st L = S holds
Sum L = Sum S
let S be Linear_Combination of RNS1; ( L = S implies Sum L = Sum S )
assume A2:
L = S
; Sum L = Sum S
consider F being FinSequence of RNS2 such that
A3:
( F is one-to-one & rng F = Carrier L & Sum L = Sum (L (#) F) )
by RLVECT_2:def 8;
reconsider E = F as FinSequence of RNS1 by A1;
A4:
Sum (L (#) F) = Sum (S (#) E)
by A2, A1, Th12, Th13;
reconsider SS = Sum L as Element of RNS1 by A1;
thus
Sum L = Sum S
by RLVECT_2:def 8, A2, A3, A4; verum