homogenious equation:

An equation of the type: $D_x y=F(\frac{y}{x})$ $\Rightarrow$ substitute $v=\frac{y}{x} \Rightarrow y=vx \Rightarrow D_x y=D_x(v)x+v$ which can be solved by $v\lq x+v=F(v) \Rightarrow \frac{D_x v}{F(v)-v} = \frac{1}{x}$