\[ a y(x) y'(x)+b y(x)^2+y(x) y''(x)-y'(x)^2=0 \] ✓ Mathematica : cpu = 0.0827801 (sec), leaf count = 28
\[\left \{\left \{y(x)\to c_2 e^{-\frac {c_1 e^{-a x}+b x}{a}}\right \}\right \}\]
✓ Maple : cpu = 0.066 (sec), leaf count = 39
\[ \left \{ y \left ( x \right ) ={1{{\rm e}^{{\frac {{{\rm e}^{-ax}}{\it \_C1}}{a}}}}{{\rm e}^{{\frac {b}{{a}^{2}}}}} \left ( {{\rm e}^{{\frac {bx}{a}}}} \right ) ^{-1} \left ( {{\rm e}^{{\frac {{\it \_C2}}{a}}}} \right ) ^{-1}} \right \} \]