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Theorem 3anbi12d 1253
Description: Deduction conjoining and adding a conjunct to equivalences. (Contributed by NM, 8-Sep-2006.)
Hypotheses
Ref Expression
3anbi12d.1 (φ → (ψχ))
3anbi12d.2 (φ → (θτ))
Assertion
Ref Expression
3anbi12d (φ → ((ψ θ η) ↔ (χ τ η)))

Proof of Theorem 3anbi12d
StepHypRef Expression
1 3anbi12d.1 . 2 (φ → (ψχ))
2 3anbi12d.2 . 2 (φ → (θτ))
3 biidd 228 . 2 (φ → (ηη))
41, 2, 33anbi123d 1252 1 (φ → ((ψ θ η) ↔ (χ τ η)))
Colors of variables: wff setvar class
Syntax hints:  wi 4  wb 176   w3a 934
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  df-3an 936
This theorem is referenced by:  3anbi1d  1256  3anbi2d  1257  enadj  6061
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