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Theorem or32 765
Description: A rearrangement of disjuncts. (Contributed by NM, 18-Oct-1995.) (Proof shortened by Andrew Salmon, 26-Jun-2011.)
Assertion
Ref Expression
or32 (((𝜑𝜓) ∨ 𝜒) ↔ ((𝜑𝜒) ∨ 𝜓))

Proof of Theorem or32
StepHypRef Expression
1 orass 762 . 2 (((𝜑𝜓) ∨ 𝜒) ↔ (𝜑 ∨ (𝜓𝜒)))
2 or12 761 . 2 ((𝜑 ∨ (𝜓𝜒)) ↔ (𝜓 ∨ (𝜑𝜒)))
3 orcom 723 . 2 ((𝜓 ∨ (𝜑𝜒)) ↔ ((𝜑𝜒) ∨ 𝜓))
41, 2, 33bitri 205 1 (((𝜑𝜓) ∨ 𝜒) ↔ ((𝜑𝜒) ∨ 𝜓))
Colors of variables: wff set class
Syntax hints:  wb 104  wo 703
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-io 704
This theorem depends on definitions:  df-bi 116
This theorem is referenced by:  xrnepnf  9724
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