Theorem bi1imp

Description: Importation inference similar to imp , except the outermost implication of the hypothesis is a biconditional. (Contributed by Alan Sare, 6-Nov-2017)

	Ref	Expression
Hypothesis	bi1imp.1	|- ( ph <-> ( ps -> ch ) )
Assertion	bi1imp	|- ( ( ph /\ ps ) -> ch )

Proof

Step	Hyp	Ref	Expression
1		bi1imp.1	|- ( ph <-> ( ps -> ch ) )
2	1	biimpi	|- ( ph -> ( ps -> ch ) )
3	2	imp	|- ( ( ph /\ ps ) -> ch )