\[ -3 y'(x)^2+2 y(x) y''(x)-4 y(x)^2=0 \] ✓ Mathematica : cpu = 0.104442 (sec), leaf count = 17
\[\left \{\left \{y(x)\to c_2 \sec ^2(x+2 c_1)\right \}\right \}\] ✓ Maple : cpu = 0.393 (sec), leaf count = 34
\[ \left \{ y \left ( x \right ) =4\, \left ( \left ( {{\it \_C1}}^{2}-{{\it \_C2}}^{2} \right ) \left ( \sin \left ( x \right ) \right ) ^{2}-2\,{\it \_C1}\,{\it \_C2}\,\sin \left ( x \right ) \cos \left ( x \right ) +{{\it \_C2}}^{2} \right ) ^{-1} \right \} \]