Theorem fneq1 5449

Description: Equality theorem for function predicate with domain. (Contributed by NM, 1-Aug-1994.)

Assertion

Ref	Expression
fneq1	|- ( F = G -> ( F Fn A <-> G Fn A ) )

Proof of Theorem fneq1

Step	Hyp	Ref	Expression
1		funeq 5377	. . 3 |- ( F = G -> ( Fun F <-> Fun G ) )
2		dmeq 4961	. . . 4 |- ( F = G -> dom F = dom G )
3	2	eqeq1d 2243	. . 3 |- ( F = G -> ( dom F = A <-> dom G = A ) )
4	1, 3	anbi12d 473	. 2 |- ( F = G -> ( ( Fun F /\ dom F = A ) <-> ( Fun G /\ dom G = A ) ) )
5		df-fn 5360	. 2 |- ( F Fn A <-> ( Fun F /\ dom F = A ) )
6		df-fn 5360	. 2 |- ( G Fn A <-> ( Fun G /\ dom G = A ) )
7	4, 5, 6	3bitr4g 223	1 |- ( F = G -> ( F Fn A <-> G Fn A ) )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   = wceq 1398   dom cdm 4754   Fun wfun 5351   Fn wfn 5352

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-io 717  ax-5 1496  ax-7 1497  ax-gen 1498  ax-ie1 1542  ax-ie2 1543  ax-8 1553  ax-10 1554  ax-11 1555  ax-i12 1556  ax-bndl 1558  ax-4 1559  ax-17 1575  ax-i9 1579  ax-ial 1583  ax-i5r 1584  ax-ext 2216

This theorem depends on definitions:  df-bi 117  df-3an 1007  df-tru 1401  df-nf 1510  df-sb 1812  df-clab 2221  df-cleq 2227  df-clel 2230  df-nfc 2375  df-v 2817  df-un 3218  df-in 3220  df-ss 3227  df-sn 3700  df-pr 3701  df-op 3703  df-br 4115  df-opab 4177  df-rel 4761  df-cnv 4762  df-co 4763  df-dm 4764  df-fun 5359  df-fn 5360

This theorem is referenced by:  fneq1d  5451  fneq1i  5455  fn0  5483  feq1  5496  foeq1  5591  f1ocnv  5632  mpteqb  5773  eufnfv  5922  uchoice  6344  tfr0dm  6566  tfrlemiex  6575  tfr1onlemsucfn  6584  tfr1onlemsucaccv  6585  tfr1onlembxssdm  6587  tfr1onlembfn  6588  tfr1onlemex  6591  tfr1onlemaccex  6592  tfr1onlemres  6593  mapval2  6925  elixp2  6950  ixpfn  6952  elixpsn  6983  cc2lem  7596  cc3  7598  lmodfopnelem1  14598