\[ y'(x)=\frac {1}{2} x \left (2 \sqrt {x^3-6 y(x)}+x\right ) \] ✓ Mathematica : cpu = 0.226266 (sec), leaf count = 33
\[\left \{\left \{y(x)\to \frac {1}{24} \left (-9 x^4+4 x^3+36 c_1 x^2-36 c_1{}^2\right )\right \}\right \}\] ✓ Maple : cpu = 0.277 (sec), leaf count = 22
\[\left \{-\frac {3 x^{2}}{2}+c_{1}-\sqrt {x^{3}-6 y \left (x \right )} = 0\right \}\]