\[ y''(x)-h\left (y'(x),a x+b y(x)\right )=0 \] ✗ Mathematica : cpu = 0.243767 (sec), leaf count = 0
DSolve[-h[Derivative[1][y][x], a*x + b*y[x]] + Derivative[2][y][x] == 0,y[x],x]
, could not solve
DSolve[-h[Derivative[1][y][x], a*x + b*y[x]] + Derivative[2][y][x] == 0, y[x], x]
✗ Maple : cpu = 0. (sec), leaf count = 0
dsolve(diff(diff(y(x),x),x)-h(diff(y(x),x),a*x+b*y(x))=0,y(x))
, result contains DESol or ODESolStruc
\[y \left (x \right ) = \left (-\frac {a \left (\int \textit {\_}b\left (\textit {\_a} \right )d \textit {\_a} +c_{1}\right )-\textit {\_a} b}{b}\right )\:\& \text {where}\:\left [\left \{\frac {d}{d \textit {\_a}}\textit {\_}b\left (\textit {\_a} \right )=-h \left (-\frac {a \textit {\_}b\left (\textit {\_a} \right )-b}{b \textit {\_}b\left (\textit {\_a} \right )}, \textit {\_a} b \right ) \textit {\_}b\left (\textit {\_a} \right )^{3}\right \}, \left \{\textit {\_a} =y \left (x \right )+\frac {a x}{b}, \textit {\_}b\left (\textit {\_a} \right )=\frac {b}{a +b \left (\frac {d}{d x}y \left (x \right )\right )}\right \}, \left \{x =\int \textit {\_}b\left (\textit {\_a} \right )d \textit {\_a} +c_{1}, y \left (x \right )=-\frac {a \left (\int \textit {\_}b\left (\textit {\_a} \right )d \textit {\_a} +c_{1}\right )-\textit {\_a} b}{b}\right \}\right ]\]