JEE Main 2021 — Application Of Derivatives Question with Solution
From: JEE Main 2021 (Online) 27th August Evening Shift
Question
A box open from top is made from a rectangular sheet of dimension a b by cutting squares each of side x from each of the four corners and folding up the flaps. If the volume of the box is maximum, then x is equal to :
Choose an option
Show full solutionCorrect option: C
Correct answer
C
Step-by-step explanation
V = l . b . h = (a 2x)(b 2x) x
V(x) = (2x a)(2x b) x
V(x) = 4x3 2(a + b)x2 + abx
Let
Now,
x =
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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.