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Theorem pm5.33 617
Description: Theorem *5.33 of [WhiteheadRussell] p. 125. (Contributed by NM, 3-Jan-2005.)
Assertion
Ref Expression
pm5.33  |-  ( (
ph  /\  ( ps  ->  ch ) )  <->  ( ph  /\  ( ( ph  /\  ps )  ->  ch )
) )

Proof of Theorem pm5.33
StepHypRef Expression
1 ibar 301 . . 3  |-  ( ph  ->  ( ps  <->  ( ph  /\ 
ps ) ) )
21imbi1d 231 . 2  |-  ( ph  ->  ( ( ps  ->  ch )  <->  ( ( ph  /\ 
ps )  ->  ch ) ) )
32pm5.32i 458 1  |-  ( (
ph  /\  ( ps  ->  ch ) )  <->  ( ph  /\  ( ( ph  /\  ps )  ->  ch )
) )
Colors of variables:    wff set class
This proof depends on syntax axioms:    -> wi 4    /\ wa 104    <-> wb 105
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108
This proof depends on definitions:  df-bi 117
This theorem is used by: (None)
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