If the function ƒ is defined by ƒ(x) = (x - a)(x - b) over (x - c), where 0 < a < b < c, for which of the following values of x is ƒ undefined?

Question

I. a
II. b
III. c
These are the answer choices:
1. None
2. I only
3. III only
4. I and II only
5. I, II, and III

Answer 1

It is undefined when x = c. That is when the denominator is zero.