Description: The square root of a nonnegative real is nonnegative. (Contributed by NM, 26-May-1999) (Revised by Mario Carneiro, 6-Sep-2013)
Ref | Expression | ||
---|---|---|---|
Hypothesis | sqrtthi.1 | |
|
Assertion | sqrtge0i | |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | sqrtthi.1 | |
|
2 | sqrtge0 | |
|
3 | 1 2 | mpan | |