ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  xorbin GIF version

Theorem xorbin 1433
Description: A consequence of exclusive or. In classical logic the converse also holds. (Contributed by Jim Kingdon, 8-Mar-2018.)
Assertion
Ref Expression
xorbin ((𝜑 ⊻ 𝜓) → (𝜑 ↔ ¬ 𝜓))

Proof of Theorem xorbin
StepHypRef Expression
1 df-xor 1425 . . 3 ((𝜑 ⊻ 𝜓) ↔ ((𝜑 ∨ 𝜓) ∧ ¬ (𝜑 ∧ 𝜓)))
2 imnan 701 . . . . 5 ((𝜑 → ¬ 𝜓) ↔ ¬ (𝜑 ∧ 𝜓))
32biimpri 133 . . . 4 (¬ (𝜑 ∧ 𝜓) → (𝜑 → ¬ 𝜓))
43adantl 277 . . 3 (((𝜑 ∨ 𝜓) ∧ ¬ (𝜑 ∧ 𝜓)) → (𝜑 → ¬ 𝜓))
51, 4sylbi 121 . 2 ((𝜑 ⊻ 𝜓) → (𝜑 → ¬ 𝜓))
6 pm2.53 734 . . . . 5 ((𝜓 ∨ 𝜑) → (¬ 𝜓 → 𝜑))
76orcoms 742 . . . 4 ((𝜑 ∨ 𝜓) → (¬ 𝜓 → 𝜑))
87adantr 276 . . 3 (((𝜑 ∨ 𝜓) ∧ ¬ (𝜑 ∧ 𝜓)) → (¬ 𝜓 → 𝜑))
91, 8sylbi 121 . 2 ((𝜑 ⊻ 𝜓) → (¬ 𝜓 → 𝜑))
105, 9impbid 129 1 ((𝜑 ⊻ 𝜓) → (𝜑 ↔ ¬ 𝜓))
Colors of variables:    wff set class
This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ∧ wa 104   ↔ wb 105   ∨ 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:  xornbi  1435  zeo4  12656  odd2np1  12659
  Copyright terms: Public domain W3C validator