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Theorem 3bitr2rd 215
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 189 . 2  |-  ( ph  ->  ( ps  <->  th )
)
4 3bitr2d.3 . 2  |-  ( ph  ->  ( th  <->  ta )
)
53, 4bitr2d 187 1  |-  ( ph  ->  ( ta  <->  ps )
)
Colors of variables: wff set class
Syntax hints:    -> wi 4    <-> wb 103
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106
This theorem depends on definitions:  df-bi 115
This theorem is referenced by:  fndmdif  5325  addsubeq4  7460  muleqadd  7895  nn0lt10b  8579  adddivflid  9444  frec2uzltd  9555  summodnegmod  10452
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