The solution of the differential equation x d y d x + 2 y = x 2 ,   ( x ≠ 0 ) with y 1 = 1 , is

The solution of the differential equation xdydx+2y=x2, (x0) with y1=1, is
  1. y=x35+15x2
  2. y=34x2+14x2
  3. y=x24+34x2
  4. y=45x3+15x2

Solution

Given, differential equation is dydx+2xy=x

This is a linear differential equation of type dydx+Py=Q, where P&Q are the functions of x or constants.

Thus, P=2x & Q=x

The integrating factor I.F.=ePdx

=e2x dx=e2lnx

=elnx2=x2.

The solution of the linear differential equation is y×I.F.=Q×I.F.dx+C 

So, the solution of the given differential equation is

yx2=x·x2dx+C

x2y=x3dx+C

Using xndx=xn+1n+1, we get

x2y=x44+C

Since y1=1

1·1=14+C

C=34

x2y=x44+34

 y=x24+34x2.

Asked in: JEE Main 2019 (09 Apr Shift 1)

Practice more Differential Equations questions on Aicharya