Question
Solve: [3Öxy + 4y - 7Öy]dx + [4x - 7Öxy + 5Öx]dy = 0.
[3Öxy + 4y - 7Öy]dx + [4x - 7Öxy + 5Öx]dy = 0
=> dy/dx = [3Öxy + 4y - 7Öy] / [-4x + 7Öxy - 5Öx]
=> dy/dx = √y/√x [(3√x + 4√y - 7) / (-4√x + 7√y - 5)]
=> (dy/√y)/(dx/√x) = [(3√x + 4√y - 7) / (-4√x + 7√y - 5)]
now take √x = X + h and √y = Y + k
you will get a homogeneous equation dY/dX = (3X+4Y+3h+4k-7)/(7Y-4X+7k-4h-5)
take 3h+4k-7 = 0 and 7k-4h-5 = 0 and solve the equation
[3Öxy + 4y - 7Öy]dx + [4x - 7Öxy + 5Öx]dy = 0
=> dy/dx = [3Öxy + 4y - 7Öy] / [-4x + 7Öxy - 5Öx]
=> dy/dx = √y/√x [(3√x + 4√y - 7) / (-4√x + 7√y - 5)]
=> (dy/√y)/(dx/√x) = [(3√x + 4√y - 7) / (-4√x + 7√y - 5)]
now take √x = X + h and √y = Y + k
you will get a homogeneous equation dY/dX = (3X+4Y+3h+4k-7)/(7Y-4X+7k-4h-5)
take 3h+4k-7 = 0 and 7k-4h-5 = 0 and solve the equation
dY/dX = (3X+4Y)/(7Y-4X)
take Y = uX then dY/dX = u + Xdu/dX
after solving put the values of X and Y in terms of x and y,