Theorem anabs1 572

Description: Absorption into embedded conjunct. (Contributed by NM, 4-Sep-1995.) (Proof shortened by Wolf Lammen, 16-Nov-2013.)

Assertion

Ref	Expression
anabs1	|- ( ( ( ph /\ ps ) /\ ph ) <-> ( ph /\ ps ) )

Proof of Theorem anabs1

Step	Hyp	Ref	Expression
1		simpl 109	. . 3 |- ( ( ph /\ ps ) -> ph )
2	1	pm4.71i 391	. 2 |- ( ( ph /\ ps ) <-> ( ( ph /\ ps ) /\ ph ) )
3	2	bicomi 132	1 |- ( ( ( ph /\ ps ) /\ ph ) <-> ( ph /\ ps ) )

Syntax hints:   /\ wa 104   <-> wb 105

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:  poirr  4309