2.1922   ODE No. 1922

\[ \left \{x'(t)=\left (\begin {array}{cc} \{ & \begin {array}{cc} \sin \left (\frac {1}{x(t)^2+y(t)^2}\right ) x(t) \left (x(t)^2+y(t)^2-1\right ) & x(t)^2+y(t)^2\neq 1 \\ 0 & \text {True} \\\end {array} \\\end {array}\right )-y(t),y'(t)=\left (\begin {array}{cc} \{ & \begin {array}{cc} \sin \left (\frac {1}{x(t)^2+y(t)^2}\right ) y(t) \left (x(t)^2+y(t)^2-1\right ) & x(t)^2+y(t)^2\neq 1 \\ 0 & \text {True} \\\end {array} \\\end {array}\right )+x(t)\right \} \]

✗ Mathematica : cpu = 5.63991 (sec), leaf count = 0

DSolve[{Derivative[1][x][t] == Piecewise[{{Sin[(x[t]^2 + y[t]^2)^(-1)]*x[t]*(-1 + x[t]^2 + y[t]^2), x[t]^2 + y[t]^2 != 1}}, 0] - y[t], Derivative[1][y][t] == Piecewise[{{Sin[(x[t]^2 + y[t]^2)^(-1)]*y[t]*(-1 + x[t]^2 + y[t]^2), x[t]^2 + y[t]^2 != 1}}, 0] + x[t]},{x[t], y[t]},t]
 

, could not solve

DSolve[{Derivative[1][x][t] == Piecewise[{{Sin[(x[t]^2 + y[t]^2)^(-1)]*x[t]*(-1 + x[t]^2 + y[t]^2), x[t]^2 + y[t]^2 != 1}}, 0] - y[t], Derivative[1][y][t] == Piecewise[{{Sin[(x[t]^2 + y[t]^2)^(-1)]*y[t]*(-1 + x[t]^2 + y[t]^2), x[t]^2 + y[t]^2 != 1}}, 0] + x[t]}, {x[t], y[t]}, t]

✗ Maple : cpu = 0. (sec), leaf count = 0

dsolve({diff(x(t),t) = -y(t)+piecewise(x(t)^2+y(t)^2 <> 1,x(t)*(x(t)^2+y(t)^2-1)*sin(1/(x(t)^2+y(t)^2))), diff(y(t),t) = x(t)+piecewise(x(t)^2+y(t)^2 <> 1,y(t)*(x(t)^2+y(t)^2-1)*sin(1/(x(t)^2+y(t)^2)))})
 

, exception

time expired