Question

What is the domain of the functionf(x)=sqrt 9x ? all real numbers all real numbers greater than but not equal to 0 all real number less than or equal to 0 all real numbers greater than or equal to 0

Answer 1

Domain : [0, ∞) x ≥ 0 (equal to 0 all real numbers greater than or equal to 0).

Explanation:

The given function is f(x) = √9x = 3√x

For this function f(x) is defined only if x ≥ 0 because for x < 0 the function is not defined.

f(-x) = 3√(-x) which is not defined.

Therefore domain of this function is domain: [0, ∞) x ≥ 0

Answer 2

The domain is all real numbers greater than or equal to zero

Explanation:

∵ f(x) = √9x

∴ The domain is all values of x ≥ 0

because if x = number less than zero it will be negative

There is no value in the real number for √-ve values

∴ The domain is all real numbers ≥ 0