JEE Main 2022 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 27 June 2022, Shift 1, Maths Q7

Question 7 of 90 in this shift, Maths question 7 of 30, Section A.

The lengths of the sides of a triangle are

10+x^2

10+x^2

and

20-2x^2

. If for

x=k

, the area of the triangle is maximum, then

3k^2

is equal to :

(1)5
(2)8
(3)10Official answer
(4)12

Official answer

Option 3

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.