\[ 12 y(x) y''(x)-15 y'(x)^2+8 y(x)^3=0 \] ✓ Mathematica : cpu = 0.324285 (sec), leaf count = 43
\[\left \{\left \{y(x)\to \frac {2304 c_1^2}{\left (3 c_1^2 x^2+6 c_2 c_1^2 x+3 c_2^2 c_1^2+128\right ){}^2}\right \}\right \}\]
✓ Maple : cpu = 0.135 (sec), leaf count = 147
\[ \left \{ -12\,{\frac {y \left ( x \right ) \left ( 8\,\sqrt {y \left ( x \right ) }-{\it \_C1} \right ) \sqrt {8\,y \left ( x \right ) -{\it \_C1}\,\sqrt {y \left ( x \right ) }}}{\sqrt {-24\, \left ( y \left ( x \right ) \right ) ^{3}+3\,{\it \_C1}\, \left ( y \left ( x \right ) \right ) ^{5/2}}{\it \_C1}\,\sqrt {\sqrt {y \left ( x \right ) } \left ( 8\,\sqrt {y \left ( x \right ) }-{\it \_C1} \right ) }}}-x-{\it \_C2}=0,12\,{\frac {y \left ( x \right ) \left ( 8\,\sqrt {y \left ( x \right ) }-{\it \_C1} \right ) \sqrt {8\,y \left ( x \right ) -{\it \_C1}\,\sqrt {y \left ( x \right ) }}}{\sqrt {-24\, \left ( y \left ( x \right ) \right ) ^{3}+3\,{\it \_C1}\, \left ( y \left ( x \right ) \right ) ^{5/2}}{\it \_C1}\,\sqrt {\sqrt {y \left ( x \right ) } \left ( 8\,\sqrt {y \left ( x \right ) }-{\it \_C1} \right ) }}}-x-{\it \_C2}=0 \right \} \]