Description: Closure law for nonnegative integer exponentiation. (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 ) |