Question #N198
The function $f(x) = \frac{x^2 + 2x - 3}{x^2 - x - 6}$ is undefined for which value of $x$?
A. -2
B. -1
C. 2
D. 3
Correct Answer is: D
A rational function is undefined when the denominator equals zero. Factoring the denominator, we get $(x+2)(x-3)=0$. Therefore, the function is undefined when $x=-2$ or $x=3$, and of these choices, only 3 is given.