\[ y''(x)=-\frac {2 x y'(x)}{x^2+1}-\frac {y(x)}{\left (x^2+1\right )^2} \] ✓ Mathematica : cpu = 0.0162712 (sec), leaf count = 31
\[\left \{\left \{y(x)\to \frac {c_1}{\sqrt {x^2+1}}+\frac {c_2 x}{\sqrt {x^2+1}}\right \}\right \}\] ✓ Maple : cpu = 0.01 (sec), leaf count = 17
\[y \relax (x ) = \frac {c_{1} x +c_{2}}{\sqrt {x^{2}+1}}\]