Description: A one-to-one function maps onto its range. (Contributed by NM, 13-Aug-2004)
Ref | Expression | ||
---|---|---|---|
Assertion | f1orn | ⊢ ( 𝐹 : 𝐴 –1-1-onto→ ran 𝐹 ↔ ( 𝐹 Fn 𝐴 ∧ Fun ◡ 𝐹 ) ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | dff1o2 | ⊢ ( 𝐹 : 𝐴 –1-1-onto→ ran 𝐹 ↔ ( 𝐹 Fn 𝐴 ∧ Fun ◡ 𝐹 ∧ ran 𝐹 = ran 𝐹 ) ) | |
2 | eqid | ⊢ ran 𝐹 = ran 𝐹 | |
3 | df-3an | ⊢ ( ( 𝐹 Fn 𝐴 ∧ Fun ◡ 𝐹 ∧ ran 𝐹 = ran 𝐹 ) ↔ ( ( 𝐹 Fn 𝐴 ∧ Fun ◡ 𝐹 ) ∧ ran 𝐹 = ran 𝐹 ) ) | |
4 | 2 3 | mpbiran2 | ⊢ ( ( 𝐹 Fn 𝐴 ∧ Fun ◡ 𝐹 ∧ ran 𝐹 = ran 𝐹 ) ↔ ( 𝐹 Fn 𝐴 ∧ Fun ◡ 𝐹 ) ) |
5 | 1 4 | bitri | ⊢ ( 𝐹 : 𝐴 –1-1-onto→ ran 𝐹 ↔ ( 𝐹 Fn 𝐴 ∧ Fun ◡ 𝐹 ) ) |