Description: Orthogonal complement of the empty set. (Contributed by NM, 31-Oct-2000) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Assertion | chocnul | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | ral0 | |
|
2 | 0ss | |
|
3 | ocel | |
|
4 | 2 3 | ax-mp | |
5 | 1 4 | mpbiran2 | |
6 | 5 | eqriv | |