Theorem foeq1 5435

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 5305	. . 3 |- ( F = G -> ( F Fn A <-> G Fn A ) )
2		rneq 4855	. . . 4 |- ( F = G -> ran F = ran G )
3	2	eqeq1d 2186	. . 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 5223	. 2 |- ( F : A -onto-> B <-> ( F Fn A /\ ran F = B ) )
6		df-fo 5223	. 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 1353   ran crn 4628   Fn wfn 5212   -onto->wfo 5215

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 709  ax-5 1447  ax-7 1448  ax-gen 1449  ax-ie1 1493  ax-ie2 1494  ax-8 1504  ax-10 1505  ax-11 1506  ax-i12 1507  ax-bndl 1509  ax-4 1510  ax-17 1526  ax-i9 1530  ax-ial 1534  ax-i5r 1535  ax-ext 2159

This theorem depends on definitions:  df-bi 117  df-3an 980  df-tru 1356  df-nf 1461  df-sb 1763  df-clab 2164  df-cleq 2170  df-clel 2173  df-nfc 2308  df-v 2740  df-un 3134  df-in 3136  df-ss 3143  df-sn 3599  df-pr 3600  df-op 3602  df-br 4005  df-opab 4066  df-rel 4634  df-cnv 4635  df-co 4636  df-dm 4637  df-rn 4638  df-fun 5219  df-fn 5220  df-fo 5223

This theorem is referenced by:  f1oeq1  5450  foeq123d  5455  resdif  5484  dif1en  6879  0ct  7106  ctmlemr  7107  ctm  7108  ctssdclemn0  7109  ctssdclemr  7111  ctssdc  7112  enumct  7114  omct  7116  ctssexmid  7148  exmidfodomrlemim  7200  ennnfonelemim  12425  ctinfomlemom  12428  ctinfom  12429  ctinf  12431  qnnen  12432  enctlem  12433  ctiunct  12441  omctfn  12444  ssomct  12446  mndfo  12840  subctctexmid  14753