Metamath Proof Explorer


Theorem mpteq2dva

Description: Slightly more general equality inference for the maps-to notation. (Contributed by Scott Fenton, 25-Apr-2012) Remove dependency on ax-10 . (Revised by SN, 11-Nov-2024)

Ref Expression
Hypothesis mpteq2dva.1
|- ( ( ph /\ x e. A ) -> B = C )
Assertion mpteq2dva
|- ( ph -> ( x e. A |-> B ) = ( x e. A |-> C ) )

Proof

Step Hyp Ref Expression
1 mpteq2dva.1
 |-  ( ( ph /\ x e. A ) -> B = C )
2 eqidd
 |-  ( ph -> A = A )
3 2 1 mpteq12dva
 |-  ( ph -> ( x e. A |-> B ) = ( x e. A |-> C ) )