Metamath Proof Explorer


Theorem mnfltd

Description: Minus infinity is less than any (finite) real. (Contributed by Glauco Siliprandi, 11-Dec-2019)

Ref Expression
Hypothesis mnfltd.a φA
Assertion mnfltd φ−∞<A

Proof

Step Hyp Ref Expression
1 mnfltd.a φA
2 mnflt A−∞<A
3 1 2 syl φ−∞<A