Digital PSAT Math Practice Question 291: Answer and Explanation

Question: 291

How many zeros does the function y = (x - 3)(x - 1)(x + 2)(x - 1) have?

• A. 1
• B. 2
• C. 3
• D. 4

Correct Answer: C

Explanation:

(C) A function will have a zero for each distinct factor. This polynomial is already factored, so you can assess its factors. It has 4 factors, but only 3 distinct factors: (x - 3), (x - 1), and (x + 2). Thus, there are 3 zeros: 3, 1, and - 2. The factor (x - 1) is repeated, meaning this zero will have a multiplicity of two.