Description: A function's value belongs to its range. (Contributed by NM, 15-Oct-1996)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | fnfvelrn | ⊢ ( ( 𝐹 Fn 𝐴 ∧ 𝐵 ∈ 𝐴 ) → ( 𝐹 ‘ 𝐵 ) ∈ ran 𝐹 ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | fvelrn | ⊢ ( ( Fun 𝐹 ∧ 𝐵 ∈ dom 𝐹 ) → ( 𝐹 ‘ 𝐵 ) ∈ ran 𝐹 ) | |
| 2 | 1 | funfni | ⊢ ( ( 𝐹 Fn 𝐴 ∧ 𝐵 ∈ 𝐴 ) → ( 𝐹 ‘ 𝐵 ) ∈ ran 𝐹 ) |