Description: The zero operator is a positive operator. (The literature calls it "positive", even though in some sense it is really "nonnegative".) Part of Example 12.2(i) in Young p. 142. (Contributed by NM, 23-Jul-2006) (New usage is discouraged.)
Ref | Expression | ||
---|---|---|---|
Assertion | 0leop | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | 0hmop | |
|
2 | leoprf | |
|
3 | 1 2 | ax-mp | |