Metamath Proof Explorer


Theorem xrltled

Description: 'Less than' implies 'less than or equal to' for extended reals. Deduction form of xrltle . (Contributed by Glauco Siliprandi, 11-Dec-2019)

Ref Expression
Hypotheses xrltled.a φ A *
xrltled.b φ B *
xrltled.altb φ A < B
Assertion xrltled φ A B

Proof

Step Hyp Ref Expression
1 xrltled.a φ A *
2 xrltled.b φ B *
3 xrltled.altb φ A < B
4 xrltle A * B * A < B A B
5 1 2 4 syl2anc φ A < B A B
6 3 5 mpd φ A B