let S be RealNormSpace-Sequence; for T being RealNormSpace
for Z being Subset of (product S)
for k being Element of dom S
for f being PartFunc of (product S),T holds f `partial| (Z,<*k*>) = f `partial| (Z,k)
let T be RealNormSpace; for Z being Subset of (product S)
for k being Element of dom S
for f being PartFunc of (product S),T holds f `partial| (Z,<*k*>) = f `partial| (Z,k)
let Z be Subset of (product S); for k being Element of dom S
for f being PartFunc of (product S),T holds f `partial| (Z,<*k*>) = f `partial| (Z,k)
let k be Element of dom S; for f being PartFunc of (product S),T holds f `partial| (Z,<*k*>) = f `partial| (Z,k)
let f be PartFunc of (product S),T; f `partial| (Z,<*k*>) = f `partial| (Z,k)
set I = <*k*>;
A1:
( len <*k*> = 1 & <*k*> . 1 = k )
by FINSEQ_1:40;
then f `partial| (Z,<*k*>) =
(PartDiffSeq (f,Z,<*k*>)) . (len <*k*>)
by Def7
.=
f `partial| (Z,k)
by A1, Def6
;
hence
f `partial| (Z,<*k*>) = f `partial| (Z,k)
; verum