Let y = y x be the solution curve of the differential equation, y 2 - x d y d x = 1 , satisfying y 0 = 1 .…

Let y=yx be the solution curve of the differential equation, y2-xdydx=1 , satisfying y0=1 . This curve intersects the X-axis at a point whose abscissa is
  1. 2-e
  2. -e
  3. 2
  4. 2+e

Solution

dxdy+x=y2

This equation is a linear differential equation of the type dxdy+Px=Q, where P=1 and Q=y2.
Integrating Factor I.F. =e1dy=ey

Now solution of the differential equation is xI.F.=PI.F.dy+C
x·ey=y2·ey·dy=y2·ey-2y·ey·dy

 x·ey=y2·ey-2y·ey+2ey+c

 x=y2-2y+2+c·e-y

Put x=0, y=1

 0=1-2+2+ce

 c=-e

Hence x=y2-2y+2+-e·e-y

On putting y=0 we get x=0-0+2+-ee-0

 x=2-e

Asked in: JEE Main 2020 (07 Jan Shift 2)

Practice more Differential Equations questions on Aicharya