[ Diff(x[1], t) = ((-1)*k[4]*k[5]*x[3]*x[1] + (-1)*k[4]*k[7]*x[4]*x[1] + (-1)*k[4]*k[2]*x[1] + 1*k[4]*k[12])/k[4],
  Diff(x[2], t) = (1*k[4]*k[5]*x[3]*x[1] + 1*k[4]*k[7]*x[4]*x[1] + (-1)*k[4]*k[1]*x[2] + (-1)*k[4]*(k[8]*x[2]*k[14] - k[9]*k[15]) + 1*k[4]*k[10]*k[15])/k[4],
  Diff(x[3], t) = ((-1)*k[4]*k[6]*x[2]^k[3]*x[3] + (-1)*k[4]*k[1]*x[3] + 1*k[4]*k[11])/k[4],
  Diff(x[4], t) = (1*k[4]*k[6]*x[2]^k[3]*x[3] + (-1)*k[4]*k[1]*x[4])/k[4],
  Diff(x[5], t) = 0,
  Diff(x[6], t) = 0 ]