JEE Main 2023 · MathsNumerical answerNumerical valueHardMulti-step

JEE Main 13 April 2023, Shift 2, Maths Q26

Question 26 of 90 in this shift, Maths question 26 of 30, Section B.

Let

f_n=\int_0^{\frac{\pi}{2}}\left(\sum_{k=1}^{n}\sin^{k-1}x\right)\left(\sum_{k=1}^{n}(2k-1)\sin^{k-1}x\right)\cos x\,dx

n\in\mathbb{N}

. Then

f_{21}-f_{20}

is equal to ______

Official answer

NTA final key.

Chapter: Integrals
Topic: Integration by Substitution
Idea tested: Odd Power of Cosine Substitution

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 42 of the 174 JEE Main shifts held from 2017 to 2026.