x^4 dy/dx + x^3y = -sec(xy)

Solve using substitution $:{\quad}y=\frac{\arcsin(\frac{1}{2x^{2}}+c_{1})}{x}+\frac{2πn}{x},y=\frac{π}{x}+\frac{\arcsin(-\frac{1}{2x^{2}}-c_{1})}{x}+\frac{2πn}{x}$