JEE Main 2021 · MathsMultiple choiceSingle correctMediumCalculation

JEE Main 4 August 2021, Shift 1, Maths Q71

Question 71 of 90 in this shift, Maths question 11 of 30, Section A.

y=y(x)

is the solution of the differential equation,

\sqrt{1-e^{2x}}\,dy-\sqrt{4-y^2}\cdot e^{x}dx=0

such that

y(0)=1

, then

y(-\log_e 2)

is equal to

(1) $-\frac{\pi}{3}$
(2) $-1$ Official answer
(3) $\frac{1}{2}$
(4) $1$

Official answer

Option 2

NTA final key.

Chapter: Differential Equations
Topic: Variable Separable Form
Idea tested: Inverse Trigonometric Form Simplification

Same topic in other shifts

All Variable Separable Form questions

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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.