JEE Main 2021MathematicsApplication Of DerivativesMaxima And MinimamediumNumerical

JEE Main 2021Application Of Derivatives Question with Solution

From: JEE Main 2021 (Online) 17th March Evening Shift

Question

Let f : [1, 1] R be defined as f(x) = ax2 + bx + c for all x[1, 1], where a, b, cR such that f(1) = 2, f'(1) = 1 for x(1, 1) the maximum value of f ''(x) is . If f(x) , x[1, 1], then the least value of is equal to _________.

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Show full solutionCorrect answer: 5
Correct answer
5

Step-by-step explanation







Given,











Now,









So, minimum = 5

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About this question

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