Metamath Proof Explorer


Theorem f1cnv

Description: The converse of an injective function is bijective. (Contributed by FL, 11-Nov-2011)

Ref Expression
Assertion f1cnv ( 𝐹 : 𝐴 –1-1→ 𝐵 → ◡ 𝐹 : ran 𝐹 –1-1-onto→ 𝐴 )

Proof

Step Hyp Ref Expression
1 f1f1orn ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵 → 𝐹 : 𝐴 –1-1-onto→ ran 𝐹 )
2 f1ocnv ⊢ ( 𝐹 : 𝐴 –1-1-onto→ ran 𝐹 → ◡ 𝐹 : ran 𝐹 –1-1-onto→ 𝐴 )
3 1 2 syl ⊢ ( 𝐹 : 𝐴 –1-1→ 𝐵 → ◡ 𝐹 : ran 𝐹 –1-1-onto→ 𝐴 )