Which expression describes the separation of variables for dydx=x2y3\frac{dy}{dx} = \frac{x^2}{y^3}dxdy=y3x2?
y3dy=x2dxy^3 dy = x^2 dxy3dy=x2dx
1y3dy=x2dx\frac{1}{y^3} dy = x^2 dxy31dy=x2dx
y3dy=1x2dxy^3 dy = \frac{1}{x^2} dxy3dy=x21dx
y3dx=x2dyy^3 dx = x^2 dyy3dx=x2dy