Metamath Proof Explorer


Theorem fneq1i

Description: Equality inference for function predicate with domain. (Contributed by Paul Chapman, 22-Jun-2011)

Ref Expression
Hypothesis fneq1i.1 𝐹 = 𝐺
Assertion fneq1i ( 𝐹 Fn 𝐴𝐺 Fn 𝐴 )

Proof

Step Hyp Ref Expression
1 fneq1i.1 𝐹 = 𝐺
2 fneq1 ( 𝐹 = 𝐺 → ( 𝐹 Fn 𝐴𝐺 Fn 𝐴 ) )
3 1 2 ax-mp ( 𝐹 Fn 𝐴𝐺 Fn 𝐴 )