\[ y''(x)-2 a y(x) y'(x)=0 \] ✓ Mathematica : cpu = 0.0634166 (sec), leaf count = 34
\[\left \{\left \{y(x)\to \frac {\sqrt {c_1} \tan \left (\sqrt {a} \sqrt {c_1} \left (c_2+x\right )\right )}{\sqrt {a}}\right \}\right \}\]
✓ Maple : cpu = 0.095 (sec), leaf count = 23
\[ \left \{ y \left ( x \right ) ={\frac {1}{a}\tan \left ( \sqrt {a{\it \_C1}} \left ( {\it \_C2}+x \right ) \right ) \sqrt {a{\it \_C1}}} \right \} \]