Description: Closure of exponentiation of reals. For integer exponents, see reexpclz . (Contributed by NM, 14-Dec-2005)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | reexpcl | ⊢ ( ( 𝐴 ∈ ℝ ∧ 𝑁 ∈ ℕ0 ) → ( 𝐴 ↑ 𝑁 ) ∈ ℝ ) |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | ax-resscn | ⊢ ℝ ⊆ ℂ | |
| 2 | remulcl | ⊢ ( ( 𝑥 ∈ ℝ ∧ 𝑦 ∈ ℝ ) → ( 𝑥 · 𝑦 ) ∈ ℝ ) | |
| 3 | 1re | ⊢ 1 ∈ ℝ | |
| 4 | 1 2 3 | expcllem | ⊢ ( ( 𝐴 ∈ ℝ ∧ 𝑁 ∈ ℕ0 ) → ( 𝐴 ↑ 𝑁 ) ∈ ℝ ) |