Metamath Proof Explorer


Theorem xrge0ge0

Description: A nonnegative extended real is nonnegative. (Contributed by Glauco Siliprandi, 11-Oct-2020)

Ref Expression
Assertion xrge0ge0 ⊢ A ∈ 0 +∞ → 0 ≤ A

Proof

Step Hyp Ref Expression
1 elxrge0 ⊢ A ∈ 0 +∞ ↔ A ∈ ℝ * ∧ 0 ≤ A
2 1 biimpi ⊢ A ∈ 0 +∞ → A ∈ ℝ * ∧ 0 ≤ A
3 2 simprd ⊢ A ∈ 0 +∞ → 0 ≤ A