Theorem fdmi 5355

Description: The domain of a mapping. (Contributed by NM, 28-Jul-2008.)

Hypothesis

Ref	Expression
fdmi.1	|- F : A --> B

Assertion

Ref	Expression
fdmi	|- dom F = A

Proof of Theorem fdmi

Step	Hyp	Ref	Expression
1		fdmi.1	. 2 |- F : A --> B
2		fdm 5353	. 2 |- ( F : A --> B -> dom F = A )
3	1, 2	ax-mp 5	1 |- dom F = A

Syntax hints:   = wceq 1348   dom cdm 4611   -->wf 5194

This theorem was proved from axioms:  ax-mp 5  ax-1 6  ax-2 7  ax-ia1 105  ax-ia2 106

This theorem depends on definitions:  df-bi 116  df-fn 5201  df-f 5202

This theorem is referenced by:  suplocexprlemdisj  7682  suplocexprlemub  7685  eluzel2  9492  inftonninf  10397  qtopbasss  13315  retopbas  13317  tgqioo  13341  dvexp  13469  efcn  13483  pilem3  13498