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Theorem pm2.45 690
Description: Theorem *2.45 of [WhiteheadRussell] p. 106. (Contributed by NM, 3-Jan-2005.)
Assertion
Ref Expression
pm2.45  |-  ( -.  ( ph  \/  ps )  ->  -.  ph )

Proof of Theorem pm2.45
StepHypRef Expression
1 orc 666 . 2  |-  ( ph  ->  ( ph  \/  ps ) )
21con3i 595 1  |-  ( -.  ( ph  \/  ps )  ->  -.  ph )
Colors of variables: wff set class
Syntax hints:   -. wn 3    -> wi 4    \/ wo 662
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-in1 577  ax-in2 578  ax-io 663
This theorem depends on definitions:  df-bi 115
This theorem is referenced by:  pm2.47  692  ioran  702  dn1dc  902  eueq3dc  2767
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