[ Eq(Derivative(x1, t), (1*k9*k1*x1*(1 - (x1 + x3)**k3/k2**k3) + (-1)*k9*k4*x1*x2 + (-1)*k9*k5*x3*x1)/k9),
  Eq(Derivative(x2, t), ((-1)*k9*k4*x1*x2 + 1*k9*k7*x3 + (-1)*k9*k8*x2)/k9),
  Eq(Derivative(x3, t), (1*k9*k4*x1*x2 + (-1)*k9*k6*x3)/k9) ]