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 ) |