Description: The ordering of the extended real number structure. (Contributed by Mario Carneiro, 21-Aug-2015)
Ref | Expression | ||
---|---|---|---|
Assertion | xrsle |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | xrex | ||
2 | 1 1 | xpex | |
3 | lerelxr | ||
4 | 2 3 | ssexi | |
5 | df-xrs | ||
6 | 5 | odrngle | |
7 | 4 6 | ax-mp |