Mathematics · Differential Equations

JEE Main 2024 — 30 January, Shift 1 — Question 9

Let y=y(x)y=y(x) be the solution of the differential equation sec⁡xd d+{2(1−x)tan⁡x+x(2−x)}\sec \mathrm{x} d \mathrm{~d}+\{2(1-\mathrm{x}) \tan \mathrm{x}+\mathrm{x}(2-\mathrm{x})\} dx=0d x=0 such that y(0)=2y(0)=2. Then y(2)y(2) is equal to :

  1. Option A:

    22

    Correct
  2. Option B:

    2{1−sin⁡(2)}2\{1-\sin (2)\}

  3. Option C:

    2{sin⁡(2)+1}2\{\sin (2)+1\}

  4. Option D:

    11

Answer: A

Step-by-step solution

dydx=2(x−1)sin⁡x+(x2−2x)cos⁡x\frac{d y}{d x}=2(x-1) \sin x+\left(x^{2}-2 x\right) \cos x

Now both side integrate y(x)=∫2(x−1)sin⁡xdx+[(x2−2x)(sin⁡x)−∫(2x−2)sin⁡xdx]y(x)=\int 2(x-1) \sin x d x+\left[\left(x^{2}-2 x\right)(\sin x)-\int(2 x-2) \sin x d x\right]

y(x)=(x2−2x)sin⁡x+λy(x)=\left(x^{2}-2 x\right) \sin x+\lambda

y(0)=0+λ⇒2=λ\mathrm{y}(0)=0+\lambda \Rightarrow 2=\lambda

y(x)=(x2−2x)sin⁡x+2y(x)=\left(x^{2}-2 x\right) \sin x+2

y(2)=2y(2)=2

Answer key and solution verified before publishing.

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Exam
JEE Main 2024
Subject
Mathematics
Chapter
Differential Equations
Topic
Methods of solving a First Order,First Degree Differential
Let y=y(x) be the solution of the differential equation sec x d d +\… | JEE Main 2024 PYQ with Solution · DhiX AI