\[ y'(x)=\frac {-\frac {5 x^3}{2}+\frac {15}{4} x^3 \cos (x)-\frac {3}{2} x^3 \cos (2 x)+\frac {1}{4} x^3 \cos (3 x)+\frac {9}{2} x^2 y(x)-6 x^2 y(x) \cos (x)+\frac {3}{2} x^2 y(x) \cos (2 x)+\frac {3 x^2}{2}+x^2 \sin (x)-2 x^2 \cos (x)+\frac {1}{2} x^2 \cos (2 x)-3 x y(x)^2-2 x y(x)+y(x)^3+y(x)^2+3 x y(x)^2 \cos (x)+2 x y(x) \cos (x)+x-x \cos (x)+1}{x} \] ✓ Mathematica : cpu = 0.156711 (sec), leaf count = 101
\[\text {Solve}\left [87 \text {RootSum}\left [-29 \text {$\#$1}^3+3 \sqrt [3]{29} \text {$\#$1}-29\& ,\frac {\log \left (\frac {3 y(x)-3 x+3 x \cos (x)+1}{\sqrt [3]{29} \sqrt [3]{\frac {1}{x^3}} x}-\text {$\#$1}\right )}{\sqrt [3]{29}-29 \text {$\#$1}^2}\& \right ]+9 c_1+29^{2/3} \left (\frac {1}{x^3}\right )^{2/3} x^2 \log (x)=0,y(x)\right ]\]
✓ Maple : cpu = 0.368 (sec), leaf count = 39
\[ \left \{ y \left ( x \right ) =-\cos \left ( x \right ) x+x-{\frac {1}{3}}+{\frac {29\,{\it RootOf} \left ( -81\,\int ^{{\it \_Z}}\! \left ( 841\,{{\it \_a}}^{3}-27\,{\it \_a}+27 \right ) ^{-1}{d{\it \_a}}+\ln \left ( x \right ) +3\,{\it \_C1} \right ) }{9}} \right \} \]