JEE Mathematics · Medium

Quadratic Equations and Inequalities: Modulus equation MCQ

Solve this quality-checked JEE multiple-choice question, then review the correct answer and explanation.

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Modulus equationMediumQuestion 220022

Question

The number of real solutions of |x² − 1| = x is:
  1. A
    0
  2. B
    1
  3. C
    2
    Correct
  4. D
    3

Correct answer

2

Explanation

Case 1: x²−1 = x (x ≥ 0 region where x²≥1): x²−x−1=0, x=(1+√5)/2 (valid). Case 2: 1−x² = x → x²+x−1=0, x=(−1+√5)/2 (positive, valid since x²<1 here). Total: 2 solutions.