JEE Main 2021MathematicsSequences and SeriesMediumMCQ

JEE Main 2021 — Sequences and Series Question with Solution

JEE Main 2021 (24 Feb Shift 2)

Question

Let a,b,c be in arithmetic progression. Let the centroid of the triangle with vertices a,c,2,b and a,b be 103,73. If α,β are the roots of the equation ax2+bx+1=0, then the value of α2+β2-αβ is:

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Show full solutionCorrect option: A
Correct answer
A-71256

Step-by-step explanation

a+2+a3=103

a=4

and c+b+b3=73

c+2b=7

also 2b=a+c

2b-a+2b=7

b=114

now 4x2+114x+1=0

 

α2+β2-αβ=α+β2-3αβ

=-11162-314

=121256-34=-71256

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About this question

This is a previous-year question from JEE Main 2021, covering the Sequences and Series 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.