The question given is
$$
f(x) = \sqrt{(x − 2)(x − 6)}
$$
I have to find the domain of this function, so I take both expressions and compute when they are greater than or equals $0$ and get
$[2,\infty) \cup [6,\infty)$,
but this is wrong; any help why?
Best Answer
Hint:
You want the product of $x-2$ and $x-6$ to be non-negative. That occurs when both are non-positive or both are non-negative.