Metamath Proof Explorer


Theorem resshom

Description: Hom is unaffected by restriction. (Contributed by Mario Carneiro, 5-Jan-2017)

Ref Expression
Hypotheses resshom.1
|- D = ( C |`s A )
resshom.2
|- H = ( Hom ` C )
Assertion resshom
|- ( A e. V -> H = ( Hom ` D ) )

Proof

Step Hyp Ref Expression
1 resshom.1
 |-  D = ( C |`s A )
2 resshom.2
 |-  H = ( Hom ` C )
3 df-hom
 |-  Hom = Slot ; 1 4
4 1nn0
 |-  1 e. NN0
5 4nn
 |-  4 e. NN
6 4 5 decnncl
 |-  ; 1 4 e. NN
7 1nn
 |-  1 e. NN
8 4nn0
 |-  4 e. NN0
9 1lt10
 |-  1 < ; 1 0
10 7 8 4 9 declti
 |-  1 < ; 1 4
11 1 2 3 6 10 resslem
 |-  ( A e. V -> H = ( Hom ` D ) )