Metamath Proof Explorer
Description: A positive real raised to a real power is positive. (Contributed by SN, 6-Apr-2023)
|
|
Ref |
Expression |
|
Hypotheses |
cxpgt0d.1 |
⊢ ( 𝜑 → 𝐴 ∈ ℝ+ ) |
|
|
cxpgt0d.2 |
⊢ ( 𝜑 → 𝑁 ∈ ℝ ) |
|
Assertion |
cxpgt0d |
⊢ ( 𝜑 → 0 < ( 𝐴 ↑𝑐 𝑁 ) ) |
Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
cxpgt0d.1 |
⊢ ( 𝜑 → 𝐴 ∈ ℝ+ ) |
2 |
|
cxpgt0d.2 |
⊢ ( 𝜑 → 𝑁 ∈ ℝ ) |
3 |
1 2
|
rpcxpcld |
⊢ ( 𝜑 → ( 𝐴 ↑𝑐 𝑁 ) ∈ ℝ+ ) |
4 |
3
|
rpgt0d |
⊢ ( 𝜑 → 0 < ( 𝐴 ↑𝑐 𝑁 ) ) |