JEE Main 2021 — Functions Question with Solution
From: JEE Main 2021 (Online) 20th July Evening Shift
Question
Let be defined by . Then the value of for which (fof)(x) = x, for all , is :
Choose an option
Show full solutionCorrect option: B
Correct answer
B5
Step-by-step explanation
..... (i)
...... (ii)
fo
From eqn (i) & (ii)
Clearly
...... (ii)
fo
From eqn (i) & (ii)
Clearly
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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.