Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert

If y=y(x) is the solution curve of the differential equation x2 dy+y-1xdx=0; x>0 and y(1)=1, then y12 is equal to :

MathematicsDifferential EquationsJEE MainJEE Main 2021 (01 Sep Shift 2)
Options:
  • A 3+e
  • B 3-e
  • C 32-1e
  • D 3+1e
Solution:
1436 Upvotes Verified Answer
The correct answer is: 3-e

x2dy+ydx=dxx

dydx+yx2=1x3

I.F=e1x2dx=e-1x

y·e-1x=e-1x·1x3dx+C

 Let -1x=t1x2dx=dt

y·e-1x=-tet·dt+C

=-tet-et+C

y·e-1x=1xe-1x+e-1x+C

 Put x=1

(1)·e-1=e-11+e-1+C

C=-e-1

Equation is y·e-1x=1xe-1x+e-1x-e-1

y=1x+1-e1xe

 At x=12y12=2+1-e2ey=3-e

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.