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Theorem 3orim123d 1260
Description: Deduction joining 3 implications to form implication of disjunctions. (Contributed by NM, 4-Apr-1997.)
Hypotheses
Ref Expression
3anim123d.1
3anim123d.2
3anim123d.3
Assertion
Ref Expression
3orim123d

Proof of Theorem 3orim123d
StepHypRef Expression
1 3anim123d.1 . . . 4
2 3anim123d.2 . . . 4
31, 2orim12d 811 . . 3
4 3anim123d.3 . . 3
53, 4orim12d 811 . 2
6 df-3or 935 . 2
7 df-3or 935 . 2
85, 6, 73imtr4g 261 1
Colors of variables: wff setvar class
Syntax hints:   wi 4   wo 357   w3o 933
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-or 359  df-an 360  df-3or 935
This theorem is referenced by:  nncdiv3  6277
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