Theorem bi3impa

Description: Similar to 3impa with implication in hypothesis replaced by biconditional. (Contributed by Alan Sare, 6-Nov-2017)

	Ref	Expression
Hypothesis	bi3impa.1	|- ( ( ( ph /\ ps ) /\ ch ) <-> th )
Assertion	bi3impa	|- ( ( ph /\ ps /\ ch ) -> th )

Proof

Step	Hyp	Ref	Expression
1		bi3impa.1	|- ( ( ( ph /\ ps ) /\ ch ) <-> th )
2	1	biimpi	|- ( ( ( ph /\ ps ) /\ ch ) -> th )
3	2	3impa	|- ( ( ph /\ ps /\ ch ) -> th )