Metamath Proof Explorer


Theorem fmptdff

Description: A version of fmptd using bound-variable hypothesis instead of a distinct variable condition for ph . (Contributed by Glauco Siliprandi, 5-Jan-2025)

Ref Expression
Hypotheses fmptdff.1
|- F/ x ph
fmptdff.2
|- F/_ x A
fmptdff.3
|- F/_ x C
fmptdff.4
|- ( ( ph /\ x e. A ) -> B e. C )
fmptdff.5
|- F = ( x e. A |-> B )
Assertion fmptdff
|- ( ph -> F : A --> C )

Proof

Step Hyp Ref Expression
1 fmptdff.1
 |-  F/ x ph
2 fmptdff.2
 |-  F/_ x A
3 fmptdff.3
 |-  F/_ x C
4 fmptdff.4
 |-  ( ( ph /\ x e. A ) -> B e. C )
5 fmptdff.5
 |-  F = ( x e. A |-> B )
6 1 4 ralrimia
 |-  ( ph -> A. x e. A B e. C )
7 2 3 5 fmptff
 |-  ( A. x e. A B e. C <-> F : A --> C )
8 6 7 sylib
 |-  ( ph -> F : A --> C )