Theorem f1dm 5427

Description: The domain of a one-to-one mapping. (Contributed by NM, 8-Mar-2014.)

Assertion

Ref	Expression
f1dm	|- ( F : A -1-1-> B -> dom F = A )

Proof of Theorem f1dm

Step	Hyp	Ref	Expression
1		f1fn 5424	. 2 |- ( F : A -1-1-> B -> F Fn A )
2		fndm 5316	. 2 |- ( F Fn A -> dom F = A )
3	1, 2	syl 14	1 |- ( F : A -1-1-> B -> dom F = A )

Syntax hints:   -> wi 4   = wceq 1353   dom cdm 4627   Fn wfn 5212   -1-1->wf1 5214

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 106  ax-ia2 107

This theorem depends on definitions:  df-bi 117  df-fn 5220  df-f 5221  df-f1 5222

This theorem is referenced by:  fun11iun  5483  tposf12  6270  f1dmvrnfibi  6943  f1vrnfibi  6944  exmidfodomrlemim  7200  hmeoimaf1o  13817  exmidsbthrlem  14773