Solve: √x−2 ≥ -1
[2,∞)
We must have x-2 ≥ 0 for √x−2 to get defined, so, x ≥ 2
Now, √x−2≥−1∀x∈[2,∞) as square roots are always non-negative
Hence x ≥ 2
Note: Some students solve it by squaring on both sides for which x-2 ≥ 1 or x ≥ 3 clearly interval [2,3) is lost.