JEE Main 2021 — Application Of Derivatives Question with Solution
From: JEE Main 2021 (Online) 26th February Evening Shift
Question
Let the normals at all the points on a given curve pass through a fixed point (a, b). If the curve passes through (3, 3) and (4, 2), and given that a 2 b = 3,
then (a2 + b2 + ab) is equal to __________.
then (a2 + b2 + ab) is equal to __________.
Enter your answer
Show full solutionCorrect answer: 9
Correct answer
9
Step-by-step explanation
Let the equation of normal is Y y = , where, m =
As it passes through (a, b)
by ..... (i)
It passes through (3, 3) & (4, 2)
.... (ii)
Also,
.... (iii)
Also, .... (iv) (given)
... (v)
As it passes through (a, b)
by ..... (i)
It passes through (3, 3) & (4, 2)
.... (ii)
Also,
.... (iii)
Also, .... (iv) (given)
... (v)
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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.