How to find the domain and solution of radical functions?

Question

for example : f(x)=(square root) x+2

Answer 1

If you are talking about Reals (not Complex), then the two rules for domains are
you cannot divide by zero, and
you cannot take an even root of a negative number.

if you meant f(x) = √(x+2), then the domain would be {x|x∈R, x ≥ -2}

If you meant f(x) = 2+ √x, then the domain would be {x|x∈R, x ≥ 0}

Answer 2

Hi Amanda,

f(x)=√(x+2)

you want  √(x+2) ≥ 0

                  x + 2 ≥ 0

                       x ≥ -2

The domain of f(x) is [-2, ∞)