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Theorem syl3anl2 1250
Description: A syllogism inference. (Contributed by NM, 24-Feb-2005.)
Hypotheses
Ref Expression
syl3anl2.1 (𝜑𝜒)
syl3anl2.2 (((𝜓𝜒𝜃) ∧ 𝜏) → 𝜂)
Assertion
Ref Expression
syl3anl2 (((𝜓𝜑𝜃) ∧ 𝜏) → 𝜂)

Proof of Theorem syl3anl2
StepHypRef Expression
1 syl3anl2.1 . . 3 (𝜑𝜒)
2 syl3anl2.2 . . . 4 (((𝜓𝜒𝜃) ∧ 𝜏) → 𝜂)
32ex 114 . . 3 ((𝜓𝜒𝜃) → (𝜏𝜂))
41, 3syl3an2 1235 . 2 ((𝜓𝜑𝜃) → (𝜏𝜂))
54imp 123 1 (((𝜓𝜑𝜃) ∧ 𝜏) → 𝜂)
Colors of variables: wff set class
Syntax hints:  wi 4  wa 103  w3a 947
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107
This theorem depends on definitions:  df-bi 116  df-3an 949
This theorem is referenced by:  syl3anr2  1254
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