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Theorem pm2.48 715
Description: Theorem *2.48 of [WhiteheadRussell] p. 107. (Contributed by NM, 3-Jan-2005.)
Assertion
Ref Expression
pm2.48 (¬ (𝜑𝜓) → (𝜑 ∨ ¬ 𝜓))

Proof of Theorem pm2.48
StepHypRef Expression
1 pm2.46 713 . 2 (¬ (𝜑𝜓) → ¬ 𝜓)
21olcd 708 1 (¬ (𝜑𝜓) → (𝜑 ∨ ¬ 𝜓))
Colors of variables: wff set class
Syntax hints:  ¬ wn 3  wi 4  wo 682
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107  ax-in1 588  ax-in2 589  ax-io 683
This theorem depends on definitions:  df-bi 116
This theorem is referenced by: (None)
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