Metamath Proof Explorer


Theorem xrnltled

Description: "Not less than" implies "less than or equal to". (Contributed by Glauco Siliprandi, 11-Dec-2019)

Ref Expression
Hypotheses xrnltled.1 ⊢ φ → A ∈ ℝ *
xrnltled.2 ⊢ φ → B ∈ ℝ *
xrnltled.3 ⊢ φ → ¬ B < A
Assertion xrnltled ⊢ φ → A ≤ B

Proof

Step Hyp Ref Expression
1 xrnltled.1 ⊢ φ → A ∈ ℝ *
2 xrnltled.2 ⊢ φ → B ∈ ℝ *
3 xrnltled.3 ⊢ φ → ¬ B < A
4 1 2 xrlenltd ⊢ φ → A ≤ B ↔ ¬ B < A
5 3 4 mpbird ⊢ φ → A ≤ B