Theorem ee3bir

Description: Right-biconditional form of e3 without virtual deduction connectives. Special theorem needed for the Virtual Deduction translation tool. (Contributed by Alan Sare, 22-Jul-2011) (Proof modification is discouraged.) (New usage is discouraged.)

	Ref	Expression
Hypotheses	ee3bir.1	|- ( ph -> ( ps -> ( ch -> th ) ) )
	ee3bir.2	|- ( ta <-> th )
Assertion	ee3bir	|- ( ph -> ( ps -> ( ch -> ta ) ) )

Proof

Step	Hyp	Ref	Expression
1		ee3bir.1	|- ( ph -> ( ps -> ( ch -> th ) ) )
2		ee3bir.2	|- ( ta <-> th )
3	2	biimpri	|- ( th -> ta )
4	1 3	syl8	|- ( ph -> ( ps -> ( ch -> ta ) ) )