JEE Main 2021 · MathsNumerical answerNumerical valueEasyCalculation

JEE Main 4 August 2021, Shift 2, Maths Q88

Question 88 of 90 in this shift, Maths question 28 of 30, Section B.

\frac{dw(t)}{dt}=t\sqrt{121-t^2}

and

w(0)=0

, then the value of

3w(\sqrt{21})

is ________.

Official answer

331

NTA final key.

Chapter: Integrals
Topic: Integration by Substitution
Idea tested: Square Root Derivative Integration Rule

Same topic in other shifts

All Integration by Substitution questions

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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.