Theorem foeq1 5591

Description: Equality theorem for onto functions. (Contributed by NM, 1-Aug-1994.)

Assertion

Ref	Expression
foeq1	|- ( F = G -> ( F : A -onto-> B <-> G : A -onto-> B ) )

Proof of Theorem foeq1

Step	Hyp	Ref	Expression
1		fneq1 5449	. . 3 |- ( F = G -> ( F Fn A <-> G Fn A ) )
2		rneq 4989	. . . 4 |- ( F = G -> ran F = ran G )
3	2	eqeq1d 2243	. . 3 |- ( F = G -> ( ran F = B <-> ran G = B ) )
4	1, 3	anbi12d 473	. 2 |- ( F = G -> ( ( F Fn A /\ ran F = B ) <-> ( G Fn A /\ ran G = B ) ) )
5		df-fo 5363	. 2 |- ( F : A -onto-> B <-> ( F Fn A /\ ran F = B ) )
6		df-fo 5363	. 2 |- ( G : A -onto-> B <-> ( G Fn A /\ ran G = B ) )
7	4, 5, 6	3bitr4g 223	1 |- ( F = G -> ( F : A -onto-> B <-> G : A -onto-> B ) )

Syntax hints:   -> wi 4   /\ wa 104   <-> wb 105   = wceq 1398   ran crn 4755   Fn wfn 5352   -onto->wfo 5355

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-rn 4765  df-fun 5359  df-fn 5360  df-fo 5363

This theorem is referenced by:  f1oeq1  5607  foeq123d  5612  resdif  5641  dif1en  7149  0ct  7411  ctmlemr  7412  ctm  7413  ctssdclemn0  7414  ctssdclemr  7416  ctssdc  7417  enumct  7419  omct  7421  ctssexmid  7454  exmidfodomrlemim  7517  nninfct  12762  ennnfonelemim  13259  ctinfomlemom  13262  ctinfom  13263  ctinf  13265  qnnen  13266  enctlem  13267  ctiunct  13275  omctfn  13278  ssomct  13280  mndfo  13700  znzrhfo  14922  subctctexmid  16900  domomsubct  16901