Theorem bj-biorfi 32568

Description: This should be labeled "biorfi" while the current biorfi 422 should be labeled "biorfri". The dual of biorf 420 is not biantr 972 but iba 524 (and ibar 525). So there should also be a "biorfr". (Note that these four statements can actually be strengthened to biconditionals.) (Contributed by BJ, 26-Oct-2019.) (Proof modification is discouraged.)

Hypothesis

Ref	Expression
bj-biorfi.1	|- -. ph

Assertion

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

Proof of Theorem bj-biorfi

Step	Hyp	Ref	Expression
1		bj-biorfi.1	. 2 |- -. ph
2		biorf 420	. 2 |- ( -. ph -> ( ps <-> ( ph \/ ps ) ) )
3	1, 2	ax-mp 5	1 |- ( ps <-> ( ph \/ ps ) )

Syntax hints:   -. wn 3   <-> wb 196   \/ wo 383

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-or 385

This theorem is referenced by:  bj-falor  32569