\[ y''(x)=-\frac {2 x y'(x)}{x^2+1}-\frac {y(x)}{\left (x^2+1\right )^2} \] ✓ Mathematica : cpu = 0.0288857 (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 = 24
\[ \left \{ y \left ( x \right ) ={{\it \_C1}\,x{\frac {1}{\sqrt {{x}^{2}+1}}}}+{{\it \_C2}{\frac {1}{\sqrt {{x}^{2}+1}}}} \right \} \]