Theorem frn

Description: The range of a mapping. (Contributed by NM, 3-Aug-1994)

	Ref	Expression
Assertion	frn	|- ( F : A --> B -> ran F C_ B )

Proof

Step	Hyp	Ref	Expression
1		df-f	|- ( F : A --> B <-> ( F Fn A /\ ran F C_ B ) )
2	1	simprbi	|- ( F : A --> B -> ran F C_ B )