Metamath Proof Explorer


Theorem reexpcl

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 )

Proof

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 )