Description: The derivative of a polynomial is a polynomial. (Contributed by Stefan O'Rear, 14-Nov-2014) (Proof shortened by Mario Carneiro, 1-Jan-2017)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | dvply2 | ⊢ ( 𝐹 ∈ ( Poly ‘ 𝑆 ) → ( ℂ D 𝐹 ) ∈ ( Poly ‘ ℂ ) ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | cnring | ⊢ ℂfld ∈ Ring | |
| 2 | cnfldbas | ⊢ ℂ = ( Base ‘ ℂfld ) | |
| 3 | 2 | subrgid | ⊢ ( ℂfld ∈ Ring → ℂ ∈ ( SubRing ‘ ℂfld ) ) |
| 4 | 1 3 | ax-mp | ⊢ ℂ ∈ ( SubRing ‘ ℂfld ) |
| 5 | plyssc | ⊢ ( Poly ‘ 𝑆 ) ⊆ ( Poly ‘ ℂ ) | |
| 6 | 5 | sseli | ⊢ ( 𝐹 ∈ ( Poly ‘ 𝑆 ) → 𝐹 ∈ ( Poly ‘ ℂ ) ) |
| 7 | dvply2g | ⊢ ( ( ℂ ∈ ( SubRing ‘ ℂfld ) ∧ 𝐹 ∈ ( Poly ‘ ℂ ) ) → ( ℂ D 𝐹 ) ∈ ( Poly ‘ ℂ ) ) | |
| 8 | 4 6 7 | sylancr | ⊢ ( 𝐹 ∈ ( Poly ‘ 𝑆 ) → ( ℂ D 𝐹 ) ∈ ( Poly ‘ ℂ ) ) |