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Theorem bi2anan9r 844
Description: Deduction joining two equivalences to form equivalence of conjunctions. (Contributed by NM, 19-Feb-1996.)
Hypotheses
Ref Expression
bi2an9.1
bi2an9.2
Assertion
Ref Expression
bi2anan9r

Proof of Theorem bi2anan9r
StepHypRef Expression
1 bi2an9.1 . . 3
2 bi2an9.2 . . 3
31, 2bi2anan9 843 . 2
43ancoms 439 1
Colors of variables: wff setvar class
Syntax hints:   wi 4   wb 176   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: (None)
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