\[ a y'(x)^2+b y(x)+y''(x)=0 \] ✗ Mathematica : cpu = 101.565 (sec), leaf count = 0 , could not solve
DSolve[b*y[x] + a*Derivative[1][y][x]^2 + Derivative[2][y][x] == 0, y[x], x]
✓ Maple : cpu = 0.174 (sec), leaf count = 79
\[ \left \{ \int ^{y \left ( x \right ) }\!-2\,{\frac {a}{\sqrt {4\,{{\rm e}^{-2\,a{\it \_a}}}{\it \_C1}\,{a}^{2}-4\,b{\it \_a}\,a+2\,b}}}{d{\it \_a}}-x-{\it \_C2}=0,\int ^{y \left ( x \right ) }\!2\,{\frac {a}{\sqrt {4\,{{\rm e}^{-2\,a{\it \_a}}}{\it \_C1}\,{a}^{2}-4\,b{\it \_a}\,a+2\,b}}}{d{\it \_a}}-x-{\it \_C2}=0 \right \} \]