Theorem fneq1 5347

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 5279	. . 3 |- ( F = G -> ( Fun F <-> Fun G ) )
2		dmeq 4867	. . . 4 |- ( F = G -> dom F = dom G )
3	2	eqeq1d 2205	. . 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 5262	. 2 |- ( F Fn A <-> ( Fun F /\ dom F = A ) )
6		df-fn 5262	. 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 1364   dom cdm 4664   Fun wfun 5253   Fn wfn 5254

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 710  ax-5 1461  ax-7 1462  ax-gen 1463  ax-ie1 1507  ax-ie2 1508  ax-8 1518  ax-10 1519  ax-11 1520  ax-i12 1521  ax-bndl 1523  ax-4 1524  ax-17 1540  ax-i9 1544  ax-ial 1548  ax-i5r 1549  ax-ext 2178

This theorem depends on definitions:  df-bi 117  df-3an 982  df-tru 1367  df-nf 1475  df-sb 1777  df-clab 2183  df-cleq 2189  df-clel 2192  df-nfc 2328  df-v 2765  df-un 3161  df-in 3163  df-ss 3170  df-sn 3629  df-pr 3630  df-op 3632  df-br 4035  df-opab 4096  df-rel 4671  df-cnv 4672  df-co 4673  df-dm 4674  df-fun 5261  df-fn 5262

This theorem is referenced by:  fneq1d  5349  fneq1i  5353  fn0  5380  feq1  5393  foeq1  5479  f1ocnv  5520  mpteqb  5655  eufnfv  5796  uchoice  6204  tfr0dm  6389  tfrlemiex  6398  tfr1onlemsucfn  6407  tfr1onlemsucaccv  6408  tfr1onlembxssdm  6410  tfr1onlembfn  6411  tfr1onlemex  6414  tfr1onlemaccex  6415  tfr1onlemres  6416  mapval2  6746  elixp2  6770  ixpfn  6772  elixpsn  6803  cc2lem  7349  cc3  7351  lmodfopnelem1  13956