Metamath Proof Explorer


Theorem f1fun

Description: A one-to-one mapping is a function. (Contributed by NM, 8-Mar-2014) (Proof shortened by Umit Teoman Dogan, 10-Jun-2026)

Ref Expression
Assertion f1fun ⊢ F : A ⟶ 1-1 B → Fun ⁡ F

Proof

Step Hyp Ref Expression
1 f1fn ⊢ F : A ⟶ 1-1 B → F Fn A
2 1 fnfund ⊢ F : A ⟶ 1-1 B → Fun ⁡ F