Metamath Proof Explorer


Theorem fneq12d

Description: Equality deduction for function predicate with domain. (Contributed by NM, 26-Jun-2011)

Ref Expression
Hypotheses fneq12d.1 φF=G
fneq12d.2 φA=B
Assertion fneq12d φFFnAGFnB

Proof

Step Hyp Ref Expression
1 fneq12d.1 φF=G
2 fneq12d.2 φA=B
3 1 fneq1d φFFnAGFnA
4 2 fneq2d φGFnAGFnB
5 3 4 bitrd φFFnAGFnB