Metamath Proof Explorer


Theorem f1of

Description: A one-to-one onto mapping is a mapping. (Contributed by NM, 12-Dec-2003)

Ref Expression
Assertion f1of F : A 1-1 onto B F : A B

Proof

Step Hyp Ref Expression
1 f1of1 F : A 1-1 onto B F : A 1-1 B
2 f1f F : A 1-1 B F : A B
3 1 2 syl F : A 1-1 onto B F : A B