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Theorem mtp-orOLD 1539
Description: Obsolete version of mtp-or 1538 as of 11-Nov-2017. (Contributed by David A. Wheeler, 3-Jul-2016.) (New usage is discouraged.) (Proof modification is discouraged.)
Hypotheses
Ref Expression
mtp-or.1 ¬ φ
mtp-or.2 (φ ψ)
Assertion
Ref Expression
mtp-orOLD ψ

Proof of Theorem mtp-orOLD
StepHypRef Expression
1 mtp-or.1 . 2 ¬ φ
2 mtp-or.2 . . 3 (φ ψ)
3 pm2.53 362 . . 3 ((φ ψ) → (¬ φψ))
42, 3ax-mp 5 . 2 φψ)
51, 4ax-mp 5 1 ψ
Colors of variables: wff setvar class
Syntax hints:  ¬ wn 3  wi 4   wo 357
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 177  df-or 359
This theorem is referenced by: (None)
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