- #1
darryw
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Homework Statement
verify the equation is homogeneous and solve.. thanks
(x^2 - 2y^2)dx + (xy)dy = 0
(x^2 - 2y^2) = -(xy)dy/dx
(x^2 - 2y^2)/-(xy) = dy/dx
-(x/y) - 2(y/x) = dy/dx
v = (y/x) .. y = vx and dy/dx = v + xv'
-(1/v) - 2v = v + xv'
x(dv/dx) + (1/v) + 3v = 0
3v + (1/v) = -x(dv/dx)
(3v + (1/v))/dv = -x/dx
(1/3v + v)dv = (1/x) dx
1/9v^3 + 1/2v^2 = ln|x| + c