Theorem simp2d

Description: Deduce a conjunct from a triple conjunction. (Contributed by NM, 4-Sep-2005)

	Ref	Expression
Hypothesis	3simp1d.1	|- ( ph -> ( ps /\ ch /\ th ) )
Assertion	simp2d	|- ( ph -> ch )

Proof

Step	Hyp	Ref	Expression
1		3simp1d.1	|- ( ph -> ( ps /\ ch /\ th ) )
2		simp2	|- ( ( ps /\ ch /\ th ) -> ch )
3	1 2	syl	|- ( ph -> ch )