Theorem bothfbothsame

Description: Given both a, b are equivalent to F. , there exists a proof for a is the same as b. (Contributed by Jarvin Udandy, 31-Aug-2016)

	Ref	Expression
Hypotheses	bothfbothsame.1	|- ( ph <-> F. )
	bothfbothsame.2	|- ( ps <-> F. )
Assertion	bothfbothsame	|- ( ph <-> ps )

Proof

Step	Hyp	Ref	Expression
1		bothfbothsame.1	|- ( ph <-> F. )
2		bothfbothsame.2	|- ( ps <-> F. )
3	1 2	bitr4i	|- ( ph <-> ps )