Description: The topology component of the extended real number structure. (Contributed by Mario Carneiro, 21-Aug-2015)
Ref | Expression | ||
---|---|---|---|
Assertion | xrstset | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | fvex | |
|
2 | df-xrs | |
|
3 | 2 | odrngtset | |
4 | 1 3 | ax-mp | |