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

Year 2026 2025 2024 Total
Questions 11 10 5 26

If α and β (α < β) are the roots of the equation (- 2 + √(3)) (| √(x) - 3 |) + (x - 6 √(x)) + (9 - 2 √(3)) = 0, x ≥ 0, then √((β)/(α)) + √(αβ) is equal to:

Solution & Explanation

Core Logic

Restructure the equation to form a quadratic in |√(x) - 3|. Notice that (x - 6√(x) + 9) = (√(x) - 3)² = |√(x) - 3|². Rewrite the given equation:

(x - 6√(x) + 9) - (2 - √(3))|√(x) - 3| - 2√(3) = 0 |√(x) - 3|² - (2 - √(3))|√(x) - 3| - 2√(3) = 0
Step 1: Solve the Quadratic

Let u = |√(x) - 3|. The equation is u² - (2 - √(3))u - 2√(3) = 0. Factorizing gives:

(u - 2)(u + √(3)) = 0

So, u = 2 or u = -√(3). Since u = |√(x) - 3| cannot be negative, we reject u = -√(3). Thus, |√(x) - 3| = 2.

Step 2: Find x (Roots)

Solve |√(x) - 3| = 2:

√(x) - 3 = 2 or √(x) - 3 = -2 √(x) = 5 or √(x) = 1

Squaring gives x = 25 or x = 1. Given α < β, we have α = 1 and β = 25.

Step 3: Evaluate Target Expression

Now compute √((β)/(α)) + √(αβ):

= √((25)/(1)) + √(1 · 25) = 5 + 5 = 10
Pattern Recognition

Grouping algebraic terms (like x - 6√(x)) and a lone constant (+9) to form perfect squares is a hallmark of radical equations disguised as quadratics.

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_2026_23_january_morning

Practice all Quadratic Equations previous-year questions →

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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%)