Question 18

Function $f$ is defined as $f(x) = \frac{1}{\sqrt{x^2 - x + n}}$ with $f(-2) = \frac{1}{2}$.

How many of the following four statements are true based on the information above?

1. $n$ is an odd number.
2. $0$ is a member of the range of function $f(x)$.
3. The function $f$ has a value of $\frac{1}{4}$ when $x = -4$.
4. The domain of function $f$ is $x < -1 \cup x > 2$.