JEE Main 2009 — Application Of Derivatives Question with Solution
From: AIEEE 2009
Question
Given such that is the only
real root of If then in the interval
real root of If then in the interval
Choose an option
Show full solutionCorrect option: A
Correct answer
A is not minimum but is the maximum of
Step-by-step explanation
We have
But
As given that
Now
As there is only one solution
therefore should not have any real roots i.e.
Hence
is an increasing function on
Similarly we can prove is decreasing on
So we can conclude that
Max and Min
is not minimum but is the maximum of
But
As given that
Now
As there is only one solution
therefore should not have any real roots i.e.
Hence
is an increasing function on
Similarly we can prove is decreasing on
So we can conclude that
Max and Min
is not minimum but is the maximum of
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This is a previous-year question from JEE Main 2009, covering the Application Of Derivatives 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.