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Quadratic Equations appeared 26 times across 3 years — 3% of Mathematics. This question is from Modulus Equations.

Year 2026 2025 2024 Total
Questions 11 10 5 26

The number of real solutions of the equation x(x² + 3|x| + 5|x - 1| + 6|x - 2|) = 0 is

Numerical Answer Type:
Enter a numerical value Answer: 1 to 1 +4 marks

Solution & Explanation

Related Formula
Zero Product Property: A · B = 0 A = 0 or B = 0
Core Logic

Given equation:

x(x² + 3|x| + 5|x - 1| + 6|x - 2|) = 0

This factors into two possibilities:

  • x = 0
  • x² + 3|x| + 5|x - 1| + 6|x - 2| = 0
Step 1: Evaluating the Modulus Term

Look at the second factor: f(x) = x² + 3|x| + 5|x - 1| + 6|x - 2|. Notice that all terms inside are strictly non-negative:

  • x² ≥ 0
  • 3|x| ≥ 0
  • 5|x - 1| ≥ 0
  • 6|x - 2| ≥ 0
  • For the sum to be 0, every single term must be simultaneously zero. x² = 0 x = 0 However, if x = 0, then 5|x-1| = 5(1) = 5 ≠ 0. Therefore, there is no real value of x that makes this entire second factor equal to zero.

Step 2: Conclusion

The only valid solution to the equation is x = 0 from the first factor. Thus, there is exactly 1 real solution.

Pattern Recognition

A sum of absolute values and squares set to 0 requires all individual components to hit 0 concurrently. If they have different zero-nodes (0, 1, 2), the sum can never be 0.

Chapter Mix

Class 11 Maths: Quadratic Equations

Reference Study Guides

More Quadratic Equations Previous-Year Questions — Page 6

Q20 jee_main_2024_31_jan_morning Sign of Quadratic Expressions
Let S be the set of positive integral values of a for which (ax² + 2(a + 1)x + 9a + 4)/(x² - 8x + 32) < 0, x in R. Then, the number of elements in S is:
  • A. 1
  • B. 0
  • C. ∞
  • D. 3

Solution

Core Logic

For the denominator x² - 8x + 32, D = 64 - 128 < 0 and a = 1 > 0. Thus, x² - 8x + 32 > 0 x in R.

Step 1: Constraint on Numerator

Since the denominator is always positive, the numerator must be strictly negative for all x in R.

ax² + 2(a + 1)x + 9a + 4 < 0 x in R

This requires a < 0 and D < 0.

Step 2: Conclusion

Since a must be strictly less than 0, there are no positive integral values of a that satisfy the condition. Hence, S is an empty set. Number of elements is 0.

Chapter Mix

Class 11 Maths: Quadratic Equations

More Quadratic Equations Questions — jee_main_2024_30_january_evening

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JEE Physics: Waves (+15.5%) | Electrostatics: Concentric Shells (-29.7%) | Modern Physics: Photoelectric Clones (+34.2%) | Mathematics: Definite Integrals (+18.1%) | Chemistry: Coordination Splitting (-11.4%) | JEE Physics: Waves (+15.5%) | Electrostatics: Concentric Shells (-29.7%) | Modern Physics: Photoelectric Clones (+34.2%) | Mathematics: Definite Integrals (+18.1%) | Chemistry: Coordination Splitting (-11.4%)