Theorem aibnbaif 41074

Description: Given a implies b, not b, there exists a proof for a is F. (Contributed by Jarvin Udandy, 1-Sep-2016.)

Hypotheses

Ref	Expression
aibnbaif.1	|- ( ph -> ps )
aibnbaif.2	|- -. ps

Assertion

Ref	Expression
aibnbaif	|- ( ph <-> F. )

Proof of Theorem aibnbaif

Step	Hyp	Ref	Expression
1		aibnbaif.1	. . 3 |- ( ph -> ps )
2		aibnbaif.2	. . 3 |- -. ps
3	1, 2	aibnbna 41073	. 2 |- -. ph
4	3	bifal 1497	1 |- ( ph <-> F. )

Syntax hints:   -. wn 3   -> wi 4   <-> wb 196   F. wfal 1488

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  df-tru 1486  df-fal 1489

This theorem is referenced by:  conimpf  41084  conimpfalt  41085  dandysum2p2e4  41165