Theorem ibdr 34142

Description: Reverse of ibd 258. (Contributed by Rodolfo Medina, 30-Sep-2010.)

Hypothesis

Ref	Expression
ibdr.1	|- ( ph -> ( ch -> ( ps <-> ch ) ) )

Assertion

Ref	Expression
ibdr	|- ( ph -> ( ch -> ps ) )

Proof of Theorem ibdr

Step	Hyp	Ref	Expression
1		ibdr.1	. . 3 |- ( ph -> ( ch -> ( ps <-> ch ) ) )
2	1	bicomdd 34138	. 2 |- ( ph -> ( ch -> ( ch <-> ps ) ) )
3	2	ibd 258	1 |- ( ph -> ( ch -> ps ) )

Syntax hints:   -> wi 4   <-> wb 196

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8

This theorem depends on definitions:  df-bi 197

This theorem is referenced by: (None)