Description: Define the set of open intervals of extended reals. (Contributed by NM, 24-Dec-2006)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | df-ioo |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 0 | cioo | ||
| 1 | vx | ||
| 2 | cxr | ||
| 3 | vy | ||
| 4 | vz | ||
| 5 | 1 | cv | |
| 6 | clt | ||
| 7 | 4 | cv | |
| 8 | 5 7 6 | wbr | |
| 9 | 3 | cv | |
| 10 | 7 9 6 | wbr | |
| 11 | 8 10 | wa | |
| 12 | 11 4 2 | crab | |
| 13 | 1 3 2 2 12 | cmpo | |
| 14 | 0 13 | wceq |