Theorem bnj290

Description: /\ -manipulation. (Contributed by Jonathan Ben-Naim, 3-Jun-2011) (New usage is discouraged.)

	Ref	Expression
Assertion	bnj290	|- ( ( ph /\ ps /\ ch /\ th ) <-> ( ph /\ ch /\ th /\ ps ) )

Proof

Step	Hyp	Ref	Expression
1		3anrot	|- ( ( ps /\ ch /\ th ) <-> ( ch /\ th /\ ps ) )
2	1	anbi2i	|- ( ( ph /\ ( ps /\ ch /\ th ) ) <-> ( ph /\ ( ch /\ th /\ ps ) ) )
3		bnj252	|- ( ( ph /\ ps /\ ch /\ th ) <-> ( ph /\ ( ps /\ ch /\ th ) ) )
4		bnj252	|- ( ( ph /\ ch /\ th /\ ps ) <-> ( ph /\ ( ch /\ th /\ ps ) ) )
5	2 3 4	3bitr4i	|- ( ( ph /\ ps /\ ch /\ th ) <-> ( ph /\ ch /\ th /\ ps ) )