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 φA*
xrnltled.2 φB*
xrnltled.3 φ¬B<A
Assertion xrnltled φAB

Proof

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