\[ y'(x)=\frac {a^3 x^3 y(x)^3+a^3 x^3 y(x)^2+3 a^2 x^2 y(x)^2+2 a^2 x^2 y(x)+a^3 x^3+a^2 x+3 a x y(x)+a x+1}{a^3 x^3} \] ✓ Mathematica : cpu = 0.215357 (sec), leaf count = 85
\[\text {Solve}\left [-\frac {29}{3} \text {RootSum}\left [-29 \text {$\#$1}^3+3 \sqrt [3]{29} \text {$\#$1}-29\& ,\frac {\log \left (\frac {\frac {a x+3}{a x}+3 y(x)}{\sqrt [3]{29}}-\text {$\#$1}\right )}{\sqrt [3]{29}-29 \text {$\#$1}^2}\& \right ]=\frac {1}{9} 29^{2/3} x+c_1,y(x)\right ]\] ✓ Maple : cpu = 0.117 (sec), leaf count = 46
\[ \left \{ y \left ( x \right ) ={\frac {29\,{\it RootOf} \left ( -81\,\int ^{{\it \_Z}}\! \left ( 841\,{{\it \_a}}^{3}-27\,{\it \_a}+27 \right ) ^{-1}{d{\it \_a}}+x+3\,{\it \_C1} \right ) ax-3\,ax-9}{9\,ax}} \right \} \]