Metamath Proof Explorer
Description: Minus infinity is less than or equal to any extended real. (Contributed by Glauco Siliprandi, 26-Jun-2021)
|
|
Ref |
Expression |
|
Hypothesis |
mnfled.1 |
⊢ ( 𝜑 → 𝐴 ∈ ℝ* ) |
|
Assertion |
mnfled |
⊢ ( 𝜑 → -∞ ≤ 𝐴 ) |
Proof
Step |
Hyp |
Ref |
Expression |
1 |
|
mnfled.1 |
⊢ ( 𝜑 → 𝐴 ∈ ℝ* ) |
2 |
|
mnfle |
⊢ ( 𝐴 ∈ ℝ* → -∞ ≤ 𝐴 ) |
3 |
1 2
|
syl |
⊢ ( 𝜑 → -∞ ≤ 𝐴 ) |