JEE Main 2026MathematicsTrigonometric Ratios & IdentitiesHardNumerical

JEE Main 2026Trigonometric Ratios & Identities Question with Solution

JEE Main 2026 (04 April Shift 1)

Question

If and , then is equal to _____.

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Show full solutionCorrect answer: 2
Correct answer
2

Step-by-step explanation

Consider the general term .

We can rewrite this by multiplying and dividing by :



Using , we get:



Applying this identity to each term of :







Adding these terms, the series telescopes:





We are given .

Substituting into the equation for :





Answer:

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About this question

This is a previous-year question from JEE Main 2026, covering the Trigonometric Ratios & Identities chapter of Mathematics. PrepSharp catalogues every PYQ from JEE Main with a verified answer key and step-by-step solution prepared by IIT alumni — so you can search by chapter, topic or year and revise efficiently.