Theorem e3bir

Description: Right biconditional form of e3 . (Contributed by Alan Sare, 15-Jun-2011) (Proof modification is discouraged.) (New usage is discouraged.)

	Ref	Expression
Hypotheses	e3bir.1	|- (. ph ,. ps ,. ch ->. th ).
	e3bir.2	|- ( ta <-> th )
Assertion	e3bir	|- (. ph ,. ps ,. ch ->. ta ).

Proof

Step	Hyp	Ref	Expression
1		e3bir.1	|- (. ph ,. ps ,. ch ->. th ).
2		e3bir.2	|- ( ta <-> th )
3	2	biimpri	|- ( th -> ta )
4	1 3	e3	|- (. ph ,. ps ,. ch ->. ta ).