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Theorem imdistand 673
Description: Distribution of implication with conjunction (deduction rule). (Contributed by NM, 27-Aug-2004.)
Hypothesis
Ref Expression
imdistand.1 ⊢ (φ → (ψ → (χ → θ)))
Assertion
Ref Expression
imdistand ⊢ (φ → ((ψ ∧ χ) → (ψ ∧ θ)))

Proof of Theorem imdistand
StepHypRef Expression
1 imdistand.1 . 2 ⊢ (φ → (ψ → (χ → θ)))
2 imdistan 670 . 2 ⊢ ((ψ → (χ → θ)) ↔ ((ψ ∧ χ) → (ψ ∧ θ)))
31, 2sylib 188 1 ⊢ (φ → ((ψ ∧ χ) → (ψ ∧ θ)))
Colors of variables:    wff setvar class
This proof depends on syntax axioms:   → wi 4   ∧ 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:  imdistanda  674  fconstfv  5457  nchoicelem19  6308
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