Theorem foeq1 5614

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 5472	. . 3 |- ( F = G -> ( F Fn A <-> G Fn A ) )
2		rneq 5011	. . . 4 |- ( F = G -> ran F = ran G )
3	2	eqeq1d 2247	. . 3 |- ( F = G -> ( ran F = B <-> ran G = B ) )
4	1, 3	anbi12d 477	. 2 |- ( F = G -> ( ( F Fn A /\ ran F = B ) <-> ( G Fn A /\ ran G = B ) ) )
5		df-fo 5386	. 2 |- ( F : A -onto-> B <-> ( F Fn A /\ ran F = B ) )
6		df-fo 5386	. 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 ) )

This proof depends on syntax axioms:   -> wi 4   /\ wa 104   <-> wb 105   = wceq 1402   ran crn 4777   Fn wfn 5375   -onto->wfo 5378

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-fo 5386

This theorem is used by:  f1oeq1  5630  foeq123d  5635  resdif  5664  mapfoss  6951  dif1en  7187  0ct  7453  ctmlemr  7454  ctm  7455  ctssdclemn0  7456  ctssdclemr  7458  ctssdc  7459  enumct  7461  omct  7463  ctssexmid  7496  exmidfodomrlemim  7559  nninfct  12843  ennnfonelemim  13373  ctinfomlemom  13376  ctinfom  13377  ctinf  13379  qnnen  13380  enctlem  13381  ctiunct  13389  omctfn  13392  ssomct  13394  mndfo  13811  znzrhfo  15092  subctctexmid  17235  domomsubct  17236