ILE Home Intuitionistic Logic Explorer < Previous   Next >
Nearby theorems
Mirrors  >  Home  >  ILE Home  >  Th. List  >  feq1 Unicode version

Theorem feq1 5519
Description: Equality theorem for functions. (Contributed by NM, 1-Aug-1994.)
Assertion
Ref Expression
feq1  |-  ( F  =  G  ->  ( F : A --> B  <->  G : A
--> B ) )

Proof of Theorem feq1
StepHypRef Expression
1 fneq1 5472 . . 3  |-  ( F  =  G  ->  ( F  Fn  A  <->  G  Fn  A ) )
2 rneq 5011 . . . 4  |-  ( F  =  G  ->  ran  F  =  ran  G )
32sseq1d 3277 . . 3  |-  ( F  =  G  ->  ( ran  F  C_  B  <->  ran  G  C_  B ) )
41, 3anbi12d 477 . 2  |-  ( F  =  G  ->  (
( F  Fn  A  /\  ran  F  C_  B
)  <->  ( G  Fn  A  /\  ran  G  C_  B ) ) )
5 df-f 5384 . 2  |-  ( F : A --> B  <->  ( F  Fn  A  /\  ran  F  C_  B ) )
6 df-f 5384 . 2  |-  ( G : A --> B  <->  ( G  Fn  A  /\  ran  G  C_  B ) )
74, 5, 63bitr4g 223 1  |-  ( F  =  G  ->  ( F : A --> B  <->  G : A
--> B ) )
Colors of variables:    wff set class
This proof depends on syntax axioms:    -> wi 4    /\ wa 104    <-> wb 105    = wceq 1402    C_ wss 3220   ran crn 4777    Fn wfn 5375   -->wf 5376
This proof depends on axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107  ax-ia3 108  ax-io 721  ax-5 1500  ax-7 1501  ax-gen 1502  ax-ie1 1546  ax-ie2 1547  ax-8 1557  ax-10 1558  ax-11 1559  ax-i12 1560  ax-bndl 1562  ax-4 1563  ax-17 1579  ax-i9 1583  ax-ial 1587  ax-i5r 1588  ax-ext 2220
This proof depends on definitions:  df-bi 117  df-3an 1011  df-tru 1405  df-nf 1514  df-sb 1816  df-clab 2225  df-cleq 2231  df-clel 2234  df-nfc 2381  df-v 2823  df-un 3224  df-in 3226  df-ss 3233  df-sn 3715  df-pr 3716  df-op 3718  df-br 4132  df-opab 4194  df-rel 4783  df-cnv 4784  df-co 4785  df-dm 4786  df-rn 4787  df-fun 5382  df-fn 5383  df-f 5384
This theorem is used by:  feq1d  5523  feq1i  5529  f00  5587  f0bi  5588  f0dom0  5589  fconstg  5592  f1eq1  5596  fconst2g  5933  tfrcllemsucfn  6629  tfrcllemsucaccv  6630  tfrcllembxssdm  6632  tfrcllembfn  6633  tfrcllemex  6636  tfrcllemaccex  6637  tfrcllemres  6638  tfrcl  6640  elmapg  6940  mapfset  6950  fsetsspwxp  6953  ac6sfi  7208  f1setfi  7322  updjud  7428  finomni  7486  exmidomni  7488  mkvprop  7504  1fv  10562  seqf1oglem2  10977  seqf1og  10978  iswrd  11327  isgrpinv  13917  isghm  14104  upxp  15515  txcn  15518  plyf  15980  griedg0prc  16713  dceqnconst  17334  dcapnconst  17335
  Copyright terms: Public domain W3C validator