\[ \boxed { 2\, \left ( {\frac {{\rm d}^{2}}{{\rm d}{x}^{2}}}y \left ( x \right ) \right ) y \left ( x \right ) -3\, \left ( {\frac {\rm d}{{\rm d}x}}y \left ( x \right ) \right ) ^{2}=0} \]
Mathematica: cpu = 0.026503 (sec), leaf count = 16 \[ \left \{\left \{y(x)\to \frac {c_2}{\left (2 c_1+x\right ){}^2}\right \}\right \} \]
Maple: cpu = 1.513 (sec), leaf count = 13 \[ \left \{ y \left ( x \right ) =4\, \left ( {\it \_C1}\,x+{\it \_C2} \right ) ^{-2} \right \} \]