Metamath Proof Explorer


Theorem mpteq2da

Description: Slightly more general equality inference for the maps-to notation. (Contributed by FL, 14-Sep-2013) (Revised by Mario Carneiro, 16-Dec-2013) (Proof shortened by SN, 11-Nov-2024)

Ref Expression
Hypotheses mpteq2da.1
|- F/ x ph
mpteq2da.2
|- ( ( ph /\ x e. A ) -> B = C )
Assertion mpteq2da
|- ( ph -> ( x e. A |-> B ) = ( x e. A |-> C ) )

Proof

Step Hyp Ref Expression
1 mpteq2da.1
 |-  F/ x ph
2 mpteq2da.2
 |-  ( ( ph /\ x e. A ) -> B = C )
3 eqidd
 |-  ( ph -> A = A )
4 1 3 2 mpteq12da
 |-  ( ph -> ( x e. A |-> B ) = ( x e. A |-> C ) )