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Theorem intnanrd 883
Description: Introduction of conjunct inside of a contradiction. (Contributed by NM, 10-Jul-2005.)
Hypothesis
Ref Expression
intnand.1 (φ → ¬ ψ)
Assertion
Ref Expression
intnanrd (φ → ¬ (ψ χ))

Proof of Theorem intnanrd
StepHypRef Expression
1 intnand.1 . 2 (φ → ¬ ψ)
2 simpl 443 . 2 ((ψ χ) → ψ)
31, 2nsyl 113 1 (φ → ¬ (ψ χ))
Colors of variables: wff setvar class
Syntax hints:  ¬ wn 3  wi 4   wa 358
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8
This theorem depends on definitions:  df-bi 177  df-an 360
This theorem is referenced by:  bianfd  892  tfinltfin  4502
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