Theorem fneq2i

Description: Equality inference for function predicate with domain. (Contributed by NM, 4-Sep-2011)

	Ref	Expression
Hypothesis	fneq2i.1	$$⊢A=B$$
Assertion	fneq2i	$$⊢FFnA\leftrightarrow FFnB$$

Proof

Step	Hyp	Ref	Expression
1		fneq2i.1	$$⊢A=B$$
2		fneq2	$$⊢A=B\to \left(FFnA\leftrightarrow FFnB\right)$$
3	1 2	ax-mp	$$⊢FFnA\leftrightarrow FFnB$$