JEE Main 2021 · MathsMultiple choiceSingle correctMediumMulti-step

JEE Main 24 February 2021, Shift 2, Maths Q78

Question 78 of 90 in this shift, Maths question 18 of 30, Section A.

If a curve

y=f(x)

passes through the point (1, 2) and satisfies

x\frac{dy}{dx}+y=bx^4

, then for what value of b,

\int_{1}^{2}f(x)\mathrm{d}x=\frac{62}{5}

(1)10Official answer
(2) $\frac{31}{5}$
(3)5
(4) $\frac{62}{5}$

Official answer

Option 1

NTA final key.

Chapter: Differential Equations
Topic: Linear Differential Equations
Idea tested: Standard Linear Form Identification

Same idea in other shifts

Asked 4× 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.