JEE Main 2020MathematicsQuadratic EquationEasyMCQ

JEE Main 2020 — Quadratic Equation Question with Solution

JEE Main 2020 (06 Sep Shift 2)

Question

If α and β are the roots of the equation 2x2x+1=1, then β is equal to :

Choose an option

Show full solutionCorrect option: B
Correct answer
B-2αα+1

Step-by-step explanation

Given equation is

2x2x+1=1⇒4x2+2x-1=0 .........(1)

roots of equation 1

are α and β

∴α+β=-12

⇒β=-12-α   ........(2)

and

4α2+2α-1=0⇒α2=14-α2 .........(3)

now

-2αα+1=-2α2-2a

=-214-α2-2α=-12-α=β

Practice this on the real CBT interface

Solve this JEE Main question (and the rest of the Quadratic Equation chapter) on PrepSharp's TCS iON-style CBT player — with timer, bookmarks and session analytics.

Solve interactively →

About this question

This is a previous-year question from JEE Main 2020, covering the Quadratic Equation 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.