Description: Closure law for nonnegative integer exponentiation. For integer exponents, see expclz . (Contributed by NM, 26-May-2005)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | expcl | ⊢ ( ( 𝐴 ∈ ℂ ∧ 𝑁 ∈ ℕ0 ) → ( 𝐴 ↑ 𝑁 ) ∈ ℂ ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ssid | ⊢ ℂ ⊆ ℂ | |
| 2 | mulcl | ⊢ ( ( 𝑥 ∈ ℂ ∧ 𝑦 ∈ ℂ ) → ( 𝑥 · 𝑦 ) ∈ ℂ ) | |
| 3 | ax-1cn | ⊢ 1 ∈ ℂ | |
| 4 | 1 2 3 | expcllem | ⊢ ( ( 𝐴 ∈ ℂ ∧ 𝑁 ∈ ℕ0 ) → ( 𝐴 ↑ 𝑁 ) ∈ ℂ ) |