JEE Main 2021MathematicsFunctionsMediumMCQ

JEE Main 2021 — Functions Question with Solution

JEE Main 2021 (01 Sep Shift 2)

Question

The range of the function f(x)=log53+cos3π4+x+cosπ4+x+cosπ4-x-cos3π4-x is :

Choose an option

Show full solutionCorrect option: B
Correct answer
B[0, 2]

Step-by-step explanation

f(x)=log5(3-2sinx+2cosx)

-2≤(-2sinx+2cosx)≤2

⇒1≤(3-2sinx+2cosx)≤5

⇒log51≤f(x)≤log55

⇒0≤f(x)≤2

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About this question

This is a previous-year question from JEE Main 2021, covering the Functions 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.