Theorem funforn 5807

Description: A function maps its domain onto its range. (Contributed by NM, 23-Jul-2004.)

Assertion

Ref	Expression
funforn

Proof of Theorem funforn

Step	Hyp	Ref	Expression
1		funfn 5622	. 2
2		dffn4 5806	. 2
3	1, 2	bitri 249	1

Syntax hints:  <->wb 184  domcdm 5004  rancrn 5005  Funwfun 5587  Fnwfn 5588  -onto->wfo 5591

This theorem is referenced by:  imacosupp  6959  ordtypelem8  7971  wdomima2g  8033  imadomg  8933  gruima  9201  oppglsm  16662  1stcrestlem  19953  dfac14  20119  qtoptop2  20200  fimacnvinrn  27475

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-3 8  ax-gen 1618  ax-ext 2435

This theorem depends on definitions:  df-bi 185  df-an 371  df-cleq 2449  df-fn 5596  df-fo 5599