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Theorem xoror 1428
Description: XOR implies OR. (Contributed by BJ, 19-Apr-2019.)
Assertion
Ref Expression
xoror ((𝜑𝜓) → (𝜑𝜓))

Proof of Theorem xoror
StepHypRef Expression
1 xoranor 1426 . 2 ((𝜑𝜓) ↔ ((𝜑𝜓) ∧ (¬ 𝜑 ∨ ¬ 𝜓)))
21simplbi 274 1 ((𝜑𝜓) → (𝜑𝜓))
Colors of variables:    wff set class
This proof depends on syntax axioms:  ¬ wn 3  wi 4  wo 720  wxo 1424
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-in1 623  ax-in2 624  ax-io 721
This proof depends on definitions:  df-bi 117  df-xor 1425
This theorem is used by:  mtpxor  1475
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