\[ \left (x^2+1\right ) x y'(x)+x^2 y(x)=0 \] ✓ Mathematica : cpu = 0.008127 (sec), leaf count = 17
\[\left \{\left \{y(x)\to \frac {c_1}{\sqrt {x^2+1}}\right \}\right \}\] ✓ Maple : cpu = 0.003 (sec), leaf count = 13
\[ \left \{ y \left ( x \right ) ={{\it \_C1}{\frac {1}{\sqrt {{x}^{2}+1}}}} \right \} \]