JEE Main 2021 · MathsMultiple choiceSingle correctHardMulti-step

JEE Main 27 August 2021, Shift 2, Maths Q62

Question 62 of 90 in this shift, Maths question 2 of 30, Section A.

The set of all values of

k > -1

, for which the equation

(3x^2 + 4x + 3)^2 - (k+1)(3x^2 + 4x + 3)(3x^2 + 4x + 2) + k(3x^2 + 4x + 2)^2 = 0

has real roots, is :

(1) $\left(1, \frac{5}{2}\right]$ Official answer
(2) $[2, 3)$
(3) $\left[-\frac{1}{2}, 1\right)$
(4) $\left(\frac{1}{2}, \frac{3}{2}\right] - \{1\}$

Official answer

Option 1

NTA final key.

Chapter: Complex Numbers and Quadratic Equations
Topic: Quadratic Roots
Idea tested: Nature of Roots

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Asked 9× in all

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.