JEE Main 2021 · MathsMultiple choiceSingle correctHardMulti-step

JEE Main 16 March 2021, Shift 2, Maths Q80

Question 80 of 90 in this shift, Maths question 20 of 30, Section A.

Let

C_1

be the curve obtained by the solution of differential equation

2xy\frac{dy}{dx}=y^2-x^2

x>0

. Let the curve

C_2

be the solution of

\frac{2xy}{x^2-y^2}=\frac{dy}{dx}

. If both the curves pass through (1, 1), then the area enclosed by the curves

C_1

and

C_2

is equal to :

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

Official answer

Option 3

NTA final key.

Chapter: Application of Integrals
Topic: Area Under Curves
Idea tested: Area Between Curves

Same idea in other shifts

Asked 12× 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 42 of the 174 JEE Main shifts held from 2017 to 2026.