Official Guide Explanation:
Problem Solving #103




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Solution and Metadata

Question: 103
Page: 75
Difficulty: 6 (Moderately Difficult)
Category 1: Algebra > Solving Equations by Factoring >
Category 2: Algebra > Solving Quadratic Equations > Difference of Squares

Explanation: First, factor x3-x:

x3-x = x(x2-1) = x(x + 1)(x - 1)

Since the expression is set equal to (x - a)(x - b)(x - c), we can rewrite the expression to look more like that:

(x - 0)(x - (-1))(x - 1)

Thus, the values of a, b, and c are 0, -1, and 1. We know that a>b>c , so b is the middle number, 0. Choice (C) is correct.

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