If the value of the integral $\int_{-1}^{1}\frac{\cos\alpha x}{1+3^x}dx$ is $\frac{2}{\pi}$. Then, a value of $\alpha$ is

JEE Main 2024 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 4 April 2024, Shift 2, Maths Q10

Question 10 of 90 in this shift, Maths question 10 of 30, Section A.

If the value of the integral

\int_{-1}^{1}\frac{\cos\alpha x}{1+3^x}dx

\frac{2}{\pi}

. Then, a value of

\alpha

(1) $\frac{\pi}{4}$
(2) $\frac{\pi}{3}$
(3) $\frac{\pi}{2}$ Official answer
(4) $\frac{\pi}{6}$

Official answer

Option 3

NTA final key.

Chapter: Integrals
Topic: Definite Integral Properties
Idea tested: Symmetric Limits with Exponential Denominator Trick

Same idea in other shifts

Asked 10× 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.