70以上 y(xy+2x^2y^2)dx+x(xy-x^2y^2)dy=0 120484

 Explanation dy dx = 2x (y x2y)2 this is separable dy dx = 1 y2 ⋅ 2x (1 x2)2 y2 dy dx = 2x (1 x2)2 ⇒ y3 3 = − 1 1 x2 C