ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  feq2 Unicode version

Theorem feq2 5466
Description: Equality theorem for functions. (Contributed by NM, 1-Aug-1994.)
Assertion
Ref Expression
feq2  |-  ( A  =  B  ->  ( F : A --> C  <->  F : B
--> C ) )

Proof of Theorem feq2
StepHypRef Expression
1 fneq2 5419 . . 3  |-  ( A  =  B  ->  ( F  Fn  A  <->  F  Fn  B ) )
21anbi1d 465 . 2  |-  ( A  =  B  ->  (
( F  Fn  A  /\  ran  F  C_  C
)  <->  ( F  Fn  B  /\  ran  F  C_  C ) ) )
3 df-f 5330 . 2  |-  ( F : A --> C  <->  ( F  Fn  A  /\  ran  F  C_  C ) )
4 df-f 5330 . 2  |-  ( F : B --> C  <->  ( F  Fn  B  /\  ran  F  C_  C ) )
52, 3, 43bitr4g 223 1  |-  ( A  =  B  ->  ( F : A --> C  <->  F : B
--> C ) )
Colors of variables: wff set class
Syntax hints:    -> wi 4    /\ wa 104    <-> wb 105    = wceq 1397    C_ wss 3200   ran crn 4726    Fn wfn 5321   -->wf 5322
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 1495  ax-gen 1497  ax-4 1558  ax-17 1574  ax-ext 2213
This theorem depends on definitions:  df-bi 117  df-cleq 2224  df-fn 5329  df-f 5330
This theorem is referenced by:  feq23  5468  feq2d  5470  feq2i  5476  f00  5528  f0dom0  5530  f1eq2  5538  fressnfv  5840  tfrcllemsucfn  6518  tfrcllemsucaccv  6519  tfrcllembxssdm  6521  tfrcllembfn  6522  tfrcllemaccex  6526  tfrcllemres  6527  tfrcldm  6528  tfrcl  6529  mapvalg  6826  map0g  6856  ac6sfi  7086  isomni  7334  ismkv  7351  iswomni  7363  isghm  13829
  Copyright terms: Public domain W3C validator