Theorem anabss4 577

Description: Absorption of antecedent into conjunction. (Contributed by NM, 20-Jul-1996.)

Hypothesis

Ref	Expression
anabss4.1	|- ( ( ( ps /\ ph ) /\ ps ) -> ch )

Assertion

Ref	Expression
anabss4	|- ( ( ph /\ ps ) -> ch )

Proof of Theorem anabss4

Step	Hyp	Ref	Expression
1		anabss4.1	. . 3 |- ( ( ( ps /\ ph ) /\ ps ) -> ch )
2	1	anabss1 576	. 2 |- ( ( ps /\ ph ) -> ch )
3	2	ancoms 268	1 |- ( ( ph /\ ps ) -> ch )

Syntax hints:   -> wi 4   /\ wa 104

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108

This theorem depends on definitions:  df-bi 117

This theorem is referenced by:  anabss7  583