Description: The square root of 2 exists and is a real number. (Contributed by NM, 3-Dec-2004)
| Ref | Expression | ||
|---|---|---|---|
| Assertion | sqrt2re | |- ( sqrt ` 2 ) e. RR |
| Step | Hyp | Ref | Expression |
|---|---|---|---|
| 1 | 2re | |- 2 e. RR |
|
| 2 | 2pos | |- 0 < 2 |
|
| 3 | 1 2 | sqrtpclii | |- ( sqrt ` 2 ) e. RR |