JEE Main 2021 · MathsMultiple choiceSingle correctEasyRecall

JEE Main 26 February 2021, Shift 2, Maths Q75

Question 75 of 90 in this shift, Maths question 15 of 30, Section A.

The triangle of maximum area that can be inscribed in a given circle of radius ‘r’ is :

(1)An isosceles triangle with base equal to $2r$ .
(2)A right angle triangle having two of its sides of length $2r$ and $r$ .
(3)An equilateral triangle of height $\frac{2r}{3}$ .
(4)An equilateral triangle having each of its side of length $\sqrt{3}\,r$ .Official answer

Official answer

Option 4

NTA final key.

Chapter: Application of Derivatives
Topic: Maxima and Minima
Idea tested: Standard Geometric Optimization Results

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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.