Theorem feq1i

Description: Equality inference for functions. (Contributed by Paul Chapman, 22-Jun-2011)

	Ref	Expression
Hypothesis	feq1i.1	$$⊢F=G$$
Assertion	feq1i	$$⊢F:A⟶B\leftrightarrow G:A⟶B$$

Proof

Step	Hyp	Ref	Expression
1		feq1i.1	$$⊢F=G$$
2		feq1	$$⊢F=G\to \left(F:A⟶B\leftrightarrow G:A⟶B\right)$$
3	1 2	ax-mp	$$⊢F:A⟶B\leftrightarrow G:A⟶B$$