\[ \left \{t^2 (1-\sin (t)) x'(t)=t^2 y(t)+t x(t) (1-2 \sin (t)),t^2 (1-\sin (t)) y'(t)=x(t) (t \cos (t)-\sin (t))+t y(t) (1-t \cos (t))\right \} \] ✓ Mathematica : cpu = 0.0214935 (sec), leaf count = 29
\[\left \{\left \{x(t)\to c_1 t^2+c_2 t,y(t)\to c_1 t+c_2 \sin (t)\right \}\right \}\] ✓ Maple : cpu = 0.1 (sec), leaf count = 23
\[\{\{x \left (t \right ) = \left (c_{1} t +c_{2}\right ) t, y \left (t \right ) = c_{1} t +c_{2} \sin \left (t \right )\}\}\]