\[ 4 y(x) y''(x)-3 y'(x)^2-12 y(x)^3=0 \] ✓ Mathematica : cpu = 0.457493 (sec), leaf count = 153
\[\left \{\left \{y(x)\to \text {InverseFunction}\left [-\frac {4 \text {$\#$1} \sqrt {\frac {4 \text {$\#$1}^{3/2}}{c_1}+1} \, _2F_1\left (\frac {1}{6},\frac {1}{2};\frac {7}{6};-\frac {4 \text {$\#$1}^{3/2}}{c_1}\right )}{\sqrt {\text {$\#$1}^{3/2} \left (4 \text {$\#$1}^{3/2}+c_1\right )}}\& \right ][c_2+x]\right \},\left \{y(x)\to \text {InverseFunction}\left [\frac {4 \text {$\#$1} \sqrt {\frac {4 \text {$\#$1}^{3/2}}{c_1}+1} \, _2F_1\left (\frac {1}{6},\frac {1}{2};\frac {7}{6};-\frac {4 \text {$\#$1}^{3/2}}{c_1}\right )}{\sqrt {\text {$\#$1}^{3/2} \left (4 \text {$\#$1}^{3/2}+c_1\right )}}\& \right ][c_2+x]\right \}\right \}\] ✓ Maple : cpu = 0.295 (sec), leaf count = 57
\[ \left \{ \int ^{y \left ( x \right ) }\!{\frac {1}{\sqrt {{\it \_C1}\,{{\it \_a}}^{{\frac {3}{2}}}+4\,{{\it \_a}}^{3}}}}{d{\it \_a}}-x-{\it \_C2}=0,\int ^{y \left ( x \right ) }\!-{\frac {1}{\sqrt {{\it \_C1}\,{{\it \_a}}^{{\frac {3}{2}}}+4\,{{\it \_a}}^{3}}}}{d{\it \_a}}-x-{\it \_C2}=0 \right \} \]