Question

What is the domain of `f(x) = sqrt(x^2-144)`?

Answer 1

`x >= 12 and x <= -12`

Explanation:

`x^2 - 144 >=0` or the value under the radical in imaginary:

`x^2 >=144`

`x >= +-sqrt144`

`x >= +-12`

`x >= 12 and x <= -12`