ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  3anbi13d Unicode version

Theorem 3anbi13d 1246
Description: Deduction conjoining and adding a conjunct to equivalences. (Contributed by NM, 8-Sep-2006.)
Hypotheses
Ref Expression
3anbi12d.1  |-  ( ph  ->  ( ps  <->  ch )
)
3anbi12d.2  |-  ( ph  ->  ( th  <->  ta )
)
Assertion
Ref Expression
3anbi13d  |-  ( ph  ->  ( ( ps  /\  et  /\  th )  <->  ( ch  /\  et  /\  ta )
) )

Proof of Theorem 3anbi13d
StepHypRef Expression
1 3anbi12d.1 . 2  |-  ( ph  ->  ( ps  <->  ch )
)
2 biidd 170 . 2  |-  ( ph  ->  ( et  <->  et )
)
3 3anbi12d.2 . 2  |-  ( ph  ->  ( th  <->  ta )
)
41, 2, 33anbi123d 1244 1  |-  ( ph  ->  ( ( ps  /\  et  /\  th )  <->  ( ch  /\  et  /\  ta )
) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    <-> wb 103    /\ w3a 920
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  df-3an 922
This theorem is referenced by:  3anbi3d  1250  tfr1onlemaccex  5997  tfrcllemaccex  6010  ltxrlt  7245
  Copyright terms: Public domain W3C validator