Theorem biort 806

Description: A wff is disjoined with truth is true.

Assertion

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

Proof of Theorem biort

Step	Hyp	Ref	Expression
1		orc 291	. 2 |- (ph -> (ph \/ ps))
2		ax-1 4	. 2 |- (ph -> ((ph \/ ps) -> ph))
3	1, 2	impbid2 576	1 |- (ph -> (ph <-> (ph \/ ps)))

Syntax hints:   -> wi 3   <-> wb 163   \/ wo 239

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

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