Description: A restriction of a function is a function. (Contributed by Glauco Siliprandi, 2-Jan-2022)
| Ref | Expression | ||
|---|---|---|---|
| Hypothesis | funresd.1 | ⊢ ( 𝜑 → Fun 𝐹 ) | |
| Assertion | funresd | ⊢ ( 𝜑 → Fun ( 𝐹 ↾ 𝐴 ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | funresd.1 | ⊢ ( 𝜑 → Fun 𝐹 ) | |
| 2 | funres | ⊢ ( Fun 𝐹 → Fun ( 𝐹 ↾ 𝐴 ) ) | |
| 3 | 1 2 | syl | ⊢ ( 𝜑 → Fun ( 𝐹 ↾ 𝐴 ) ) |