Description: Minus infinity is less than any (finite) real. (Contributed by Glauco Siliprandi, 11-Dec-2019)
Ref | Expression | ||
---|---|---|---|
Hypothesis | mnfltd.a | |- ( ph -> A e. RR ) |
|
Assertion | mnfltd | |- ( ph -> -oo < A ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | mnfltd.a | |- ( ph -> A e. RR ) |
|
2 | mnflt | |- ( A e. RR -> -oo < A ) |
|
3 | 1 2 | syl | |- ( ph -> -oo < A ) |