Question

Find the doamin of f(x) = √([x] – 2) 

Answer 1

We have f(x) = [x] – 2

⇒  [x] – 2 ≥ 0

⇒  [x] ≥ 2

⇒ x ≥ 2

⇒  x ∈ [2, ∞)

Thus, D_f = [2, ∞)