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Theorem f1oeq2 5496
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 5462 . . 3  |-  ( A  =  B  ->  ( F : A -1-1-> C  <->  F : B -1-1-> C ) )
2 foeq2 5480 . . 3  |-  ( A  =  B  ->  ( F : A -onto-> C  <->  F : B -onto-> C ) )
31, 2anbi12d 473 . 2  |-  ( A  =  B  ->  (
( F : A -1-1-> C  /\  F : A -onto-> C )  <->  ( F : B -1-1-> C  /\  F : B -onto-> C ) ) )
4 df-f1o 5266 . 2  |-  ( F : A -1-1-onto-> C  <->  ( F : A -1-1-> C  /\  F : A -onto-> C ) )
5 df-f1o 5266 . 2  |-  ( F : B -1-1-onto-> C  <->  ( F : B -1-1-> C  /\  F : B -onto-> C ) )
63, 4, 53bitr4g 223 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 104    <-> wb 105    = wceq 1364   -1-1->wf1 5256   -onto->wfo 5257   -1-1-onto->wf1o 5258
This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-5 1461  ax-gen 1463  ax-4 1524  ax-17 1540  ax-ext 2178
This theorem depends on definitions:  df-bi 117  df-cleq 2189  df-fn 5262  df-f 5263  df-f1 5264  df-fo 5265  df-f1o 5266
This theorem is referenced by:  f1oeq23  5498  f1oeq123d  5501  f1oeq2d  5503  f1osng  5548  isoeq4  5854  bren  6815  f1dmvrnfibi  7019  summodclem3  11562  summodclem2a  11563  summodc  11565  fsum3  11569  fsumf1o  11572  sumsnf  11591  fprodf1o  11770  prodsnf  11774  znfi  14287  znhash  14288
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