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Theorem 3bitr2rd 216
Description: Deduction from transitivity of biconditional. (Contributed by NM, 4-Aug-2006.)
Hypotheses
Ref Expression
3bitr2d.1  |-  ( ph  ->  ( ps  <->  ch )
)
3bitr2d.2  |-  ( ph  ->  ( th  <->  ch )
)
3bitr2d.3  |-  ( ph  ->  ( th  <->  ta )
)
Assertion
Ref Expression
3bitr2rd  |-  ( ph  ->  ( ta  <->  ps )
)

Proof of Theorem 3bitr2rd
StepHypRef Expression
1 3bitr2d.1 . . 3  |-  ( ph  ->  ( ps  <->  ch )
)
2 3bitr2d.2 . . 3  |-  ( ph  ->  ( th  <->  ch )
)
31, 2bitr4d 190 . 2  |-  ( ph  ->  ( ps  <->  th )
)
4 3bitr2d.3 . 2  |-  ( ph  ->  ( th  <->  ta )
)
53, 4bitr2d 188 1  |-  ( ph  ->  ( ta  <->  ps )
)
Colors of variables: wff set class
Syntax hints:    -> wi 4    <-> wb 104
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106  ax-ia3 107
This theorem depends on definitions:  df-bi 116
This theorem is referenced by:  fndmdif  5531  addsubeq4  7999  muleqadd  8451  nn0lt10b  9153  adddivflid  10094  frec2uzltd  10205  mul0inf  11042  summodnegmod  11553  iooref1o  13419
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