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Theorem f1oeq2 5149
Description: Equality theorem for one-to-one onto functions. (Contributed by NM, 10-Feb-1997.)
Assertion
Ref Expression
f1oeq2  |-  ( A  =  B  ->  ( F : A -1-1-onto-> C  <->  F : B -1-1-onto-> C ) )

Proof of Theorem f1oeq2
StepHypRef Expression
1 f1eq2 5119 . . 3  |-  ( A  =  B  ->  ( F : A -1-1-> C  <->  F : B -1-1-> C ) )
2 foeq2 5134 . . 3  |-  ( A  =  B  ->  ( F : A -onto-> C  <->  F : B -onto-> C ) )
31, 2anbi12d 457 . 2  |-  ( A  =  B  ->  (
( F : A -1-1-> C  /\  F : A -onto-> C )  <->  ( F : B -1-1-> C  /\  F : B -onto-> C ) ) )
4 df-f1o 4939 . 2  |-  ( F : A -1-1-onto-> C  <->  ( F : A -1-1-> C  /\  F : A -onto-> C ) )
5 df-f1o 4939 . 2  |-  ( F : B -1-1-onto-> C  <->  ( F : B -1-1-> C  /\  F : B -onto-> C ) )
63, 4, 53bitr4g 221 1  |-  ( A  =  B  ->  ( F : A -1-1-onto-> C  <->  F : B -1-1-onto-> C ) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 102    <-> wb 103    = wceq 1285   -1-1->wf1 4929   -onto->wfo 4930   -1-1-onto->wf1o 4931
This theorem was proved from axioms:  ax-1 5  ax-2 6  ax-mp 7  ax-ia1 104  ax-ia2 105  ax-ia3 106  ax-5 1377  ax-gen 1379  ax-4 1441  ax-17 1460  ax-ext 2064
This theorem depends on definitions:  df-bi 115  df-cleq 2075  df-fn 4935  df-f 4936  df-f1 4937  df-fo 4938  df-f1o 4939
This theorem is referenced by:  f1oeq23  5151  f1oeq123d  5154  f1osng  5198  isoeq4  5475  bren  6294  f1dmvrnfibi  6452
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