JEE Main 2021 · MathsMultiple choiceSingle correctEasyApplication

JEE Main 3 August 2021, Shift 2, Maths Q62

Question 62 of 90 in this shift, Maths question 2 of 30, Section A.

If the equations

2x^2 + kx - 5 = 0

and

x^2 - 3x - 4 = 0

have one root in common, then a value of '

k

' is

(1) $-2$
(2) $3$
(3) $-3$ Official answer
(4) $2$

Official answer

Option 3

NTA final key.

Chapter: Complex Numbers and Quadratic Equations
Topic: Quadratic Roots
Idea tested: Common Root Condition

Same idea in other shifts

Asked 5× in all

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Question text from the official JEE Main paper published by NTA; answer from the final answer key. Chapter, topic and idea tags, difficulty and skill are Lumi’s. Lumi analyses 108 of the 174 JEE Main shifts held from 2017 to 2026.