Theorem facrm 14290

Description: False can be removed from a disjunction.

Assertion

Ref	Expression
facrm	|- (( F. \/ ph) <-> ph)

Proof of Theorem facrm

Step	Hyp	Ref	Expression
1		fampany 14288	. . 3 |- ( F. -> ph)
2		id 73	. . 3 |- (ph -> ph)
3	1, 2	jaoi 368	. 2 |- (( F. \/ ph) -> ph)
4		olc 290	. 2 |- (ph -> ( F. \/ ph))
5	3, 4	impbii 174	1 |- (( F. \/ ph) <-> ph)

Syntax hints:   <-> wb 163   \/ wo 239   F. wfal 1261

This theorem was proved from axioms:  ax-1 4  ax-2 5  ax-3 6  ax-mp 7

This theorem depends on definitions:  df-bi 164  df-or 241  df-an 242  df-tru 1262  df-fal 1263

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