JEE Main 2021 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 27 August 2021, Shift 1, Maths Q66

Question 66 of 90 in this shift, Maths question 6 of 30, Section A.

A wire of length 20 m is to be cut into two pieces. One of the pieces is to be made into a square and the other into a regular hexagon. Then the length of the side (in meters) of the hexagon, so that the combined area of the square and the hexagon is minimum, is :

(1) $\frac{5}{2+\sqrt{3}}$
(2) $\frac{5}{3+\sqrt{3}}$
(3) $\frac{10}{3+2\sqrt{3}}$ Official answer
(4) $\frac{10}{2+3\sqrt{3}}$

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.