Q.

The Solution curve of the differential equation 2y=dydx+3=5dydx, passing through the point (0, 1) is a conic, whose vertex lies on the line:           [2024]

1 2x + 3y = –6  
2 2x + 3y = 6  
3 2x + 3y = –9  
4 2x + 3y = 9  

Ans.

(4)

We have, 2ydydx+3=5dydx

  2ydy + 3dx = 5dy

Integrating both sides, we get

y2 + 3x = 5y + c

Now, at point (0, 1) i.e., at x = 0, y = 1, we have

1 + 0 = 5 + c c = –4

So, y2 - 5y = -3x - 4

  y2 - 5y + 254 - 254 = -3x - 4

  (y - 52)2 = -3x + 94  (y - 52)2 = -3(x - 34)

Vertex = (34, 52), Which satisfies by 2x + 3y = 9.