JEE Main 2021 · MathsMultiple choiceSingle correctMediumApplication

JEE Main 27 August 2021, Shift 1, Maths Q61

Question 61 of 90 in this shift, Maths question 1 of 30, Section A.

x^2+9y^2-4x+3=0

x, y \in \mathbb{R}

, then

x

and

y

respectively lie in the intervals :

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

Official answer

Option 2

NTA final key.

Chapter: Relations and Functions
Topic: Quadratic Roots
Idea tested: Nature of Roots

Same idea in other shifts

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.