JEE Main 2021 · MathsMultiple choiceSingle correctHardMulti-step

JEE Main 18 March 2021, Shift 2, Maths Q68

Question 68 of 90 in this shift, Maths question 8 of 30, Section A.

Let a tangent be drawn to the ellipse

\frac{x^2}{27}+y^2=1

(3\sqrt{3}\cos\theta,\sin\theta)

where

\theta\in\left(0,\frac{\pi}{2}\right)

. Then the value of

\theta

such that the sum of intercepts on axes made by this tangent is minimum is equal to :

(1) $\frac{\pi}{3}$
(2) $\frac{\pi}{6}$ Official answer
(3) $\frac{\pi}{8}$
(4) $\frac{\pi}{4}$

Official answer

Option 2

NTA final key.

Chapter: Application of Derivatives
Topic: Maxima and Minima
Idea tested: Optimization Problems

Same idea in other shifts

Asked 13× 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.