Theorem foeq1 5473

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 5343	. . 3 |- ( F = G -> ( F Fn A <-> G Fn A ) )
2		rneq 4890	. . . 4 |- ( F = G -> ran F = ran G )
3	2	eqeq1d 2202	. . 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 5261	. 2 |- ( F : A -onto-> B <-> ( F Fn A /\ ran F = B ) )
6		df-fo 5261	. 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 1364   ran crn 4661   Fn wfn 5250   -onto->wfo 5253

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 1458  ax-7 1459  ax-gen 1460  ax-ie1 1504  ax-ie2 1505  ax-8 1515  ax-10 1516  ax-11 1517  ax-i12 1518  ax-bndl 1520  ax-4 1521  ax-17 1537  ax-i9 1541  ax-ial 1545  ax-i5r 1546  ax-ext 2175

This theorem depends on definitions:  df-bi 117  df-3an 982  df-tru 1367  df-nf 1472  df-sb 1774  df-clab 2180  df-cleq 2186  df-clel 2189  df-nfc 2325  df-v 2762  df-un 3158  df-in 3160  df-ss 3167  df-sn 3625  df-pr 3626  df-op 3628  df-br 4031  df-opab 4092  df-rel 4667  df-cnv 4668  df-co 4669  df-dm 4670  df-rn 4671  df-fun 5257  df-fn 5258  df-fo 5261

This theorem is referenced by:  f1oeq1  5489  foeq123d  5494  resdif  5523  dif1en  6937  0ct  7168  ctmlemr  7169  ctm  7170  ctssdclemn0  7171  ctssdclemr  7173  ctssdc  7174  enumct  7176  omct  7178  ctssexmid  7211  exmidfodomrlemim  7263  nninfct  12181  ennnfonelemim  12584  ctinfomlemom  12587  ctinfom  12588  ctinf  12590  qnnen  12591  enctlem  12592  ctiunct  12600  omctfn  12603  ssomct  12605  mndfo  13023  znzrhfo  14147  subctctexmid  15561