JEE Main 2020MathematicsSequences And SeriesArithmetic ProgressionmediumMCQ

JEE Main 2020Sequences And Series Question with Solution

From: JEE Main 2020 (Online) 8th January Morning Slot

Question

Let ƒ : R R be such that for all x R
(21+x + 21–x), ƒ(x) and (3x + 3–x) are in A.P.,
then the minimum value of ƒ(x) is

Choose an option

Show full solutionCorrect option: C
Correct answer
C3

Step-by-step explanation

f(x) =

As we know, A.M > G.M

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About this question

This is a previous-year question from JEE Main 2020, covering the Sequences And Series 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.