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Theorem 3bitr2rd 206
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 180 . 2  |-  ( ph  ->  ( ps  <->  th )
)
4 3bitr2d.3 . 2  |-  ( ph  ->  ( th  <->  ta )
)
53, 4bitr2d 178 1  |-  ( ph  ->  ( ta  <->  ps )
)
Colors of variables: wff set class
Syntax hints:    -> wi 4    <-> wb 98
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 99  ax-ia2 100  ax-ia3 101
This theorem depends on definitions:  df-bi 110
This theorem is referenced by:  fndmdif  5272  addsubeq4  7226  muleqadd  7649  nn0lt10b  8321  adddivflid  9134  frec2uzltd  9189
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