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 *
xrnltled.2 φ B *
xrnltled.3 φ ¬ B < A
Assertion xrnltled φ A B

Proof

Step Hyp Ref Expression
1 xrnltled.1 φ A *
2 xrnltled.2 φ B *
3 xrnltled.3 φ ¬ B < A
4 1 2 xrlenltd φ A B ¬ B < A
5 3 4 mpbird φ A B