JEE Main 2020MathematicsTrigonometric Ratios & IdentitiesEasyMCQ

JEE Main 2020 — Trigonometric Ratios & Identities Question with Solution

JEE Main 2020 (05 Sep Shift 2)

Question

If L=sin2π16-sin2π8 and M=cos2π16-sin2π8

Choose an option

Show full solutionCorrect option: D
Correct answer
DM=122+12cosπ8

Step-by-step explanation

L=sinπ16+π8sinπ16-π8
=sin3π16·sin-π16

=12cos3π16+π16-cos3π16-π16=1212-cosπ8
M=cosπ16+π8cosπ16-π8

=cos3π16·cos-π16
=12cos3π16+π16+cos3π16-π16=1212+cosπ8

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About this question

This is a previous-year question from JEE Main 2020, 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.