JEE Main 2022MathematicsFunctionsMediumMCQ

JEE Main 2022 — Functions Question with Solution

JEE Main 2022 (26 Jun Shift 1)

Question

Let fx=x-1x+1, x∈R-{0,-1,1) . If fn+1x=  ffnx for all n∈N, then f66+f77 is equal to

Choose an option

Show full solutionCorrect option: B
Correct answer
B-32

Step-by-step explanation

Given fx=x-1x+1=f1x

⇒f2x=ffx=x-1x+1-1x-1x+1+1=-1x

Now f3x=ff2x=f-1x=x+11-x

⇒f4x=fx+11-x=-1x

⇒ f6x=-1x⇒f66=-16

So f7x=-1x=x+11-x

⇒f77=8-6=-43

∴-16+-43=-32

Practice this on the real CBT interface

Solve this JEE Main question (and the rest of the Functions chapter) on PrepSharp's TCS iON-style CBT player — with timer, bookmarks and session analytics.

Solve interactively →

About this question

This is a previous-year question from JEE Main 2022, 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.