\[ \left \{\left (t^2+1\right ) x'(t)=y(t)-t x(t),\left (t^2+1\right ) y'(t)=-x(t)-t y(t)\right \} \] ✓ Mathematica : cpu = 0.0136025 (sec), leaf count = 39
\[\left \{\left \{x(t)\to \frac {c_2 t+c_1}{t^2+1},y(t)\to \frac {c_2-c_1 t}{t^2+1}\right \}\right \}\]
✓ Maple : cpu = 0.044 (sec), leaf count = 35
\[ \left \{ \left \{ x \left ( t \right ) ={\frac {{\it \_C1}\,t+{\it \_C2}}{{t}^{2}+1}},y \left ( t \right ) ={\frac {-{\it \_C2}\,t+{\it \_C1}}{{t}^{2}+1}} \right \} \right \} \]