1)

The solution of the differential equation  ydxxdy+3x2y2ex3dx=0 satisfying y=1 when x=1, is 


A) y(ex3(1+2e))x=0

B) y(ex3+(1e))+x=0

C) y(ex3+(1+e))x=0

D) y(ex3(1+e))+x=0

Answer:

Option D

Explanation:

 We have,

ydxxdy+3x2y2ex3dx=0

 

ydxxdyy2+3x2ex3dx=0

     d(xy)+d(ex3)=0

 On integrating  , we get

 xy+ex3=c

 putting x=y=1, we get

                         c=1+e

       xy+ex3 =1+e

 x+y(ex3(1+e))+x=0