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Theorem xordi 865
Description: Conjunction distributes over exclusive-or, using ¬ (φ ↔ ψ) to express exclusive-or. This is one way to interpret the distributive law of multiplication over addition in modulo 2 arithmetic. (Contributed by NM, 3-Oct-2008.)
Assertion
Ref Expression
xordi ⊢ ((φ ∧ ¬ (ψ ↔ χ)) ↔ ¬ ((φ ∧ ψ) ↔ (φ ∧ χ)))

Proof of Theorem xordi
StepHypRef Expression
1 annim 414 . 2 ⊢ ((φ ∧ ¬ (ψ ↔ χ)) ↔ ¬ (φ → (ψ ↔ χ)))
2 pm5.32 617 . 2 ⊢ ((φ → (ψ ↔ χ)) ↔ ((φ ∧ ψ) ↔ (φ ∧ χ)))
31, 2xchbinx 301 1 ⊢ ((φ ∧ ¬ (ψ ↔ χ)) ↔ ¬ ((φ ∧ ψ) ↔ (φ ∧ χ)))
Colors of variables:    wff setvar class
This proof depends on syntax axioms:  ¬ wn 3   → wi 4   ↔ wb 176   ∧ wa 358
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8
This proof depends on definitions:  df-bi 177  df-an 360
This theorem is used by: (None)
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