{ diff(x1, t) = 0,
  diff(x2, t) = (2*k12*(k9*k14/(k14 + k10*(1 + k15/k11))*k1 + k9*k14/(k14 + k10*(1 + k15/k11))*k13 - abs(k9*k14/(k14 + k10*(1 + k15/k11))*k1 - k9*k14/(k14 + k10*(1 + k15/k11))*k13))/2 + 3/2*k12*21/100*k15/k11/(k14/k10)*(k9*k14/(k14 + k10*(1 + k15/k11))*k1 + k9*k14/(k14 + k10*(1 + k15/k11))*k13 - abs(k9*k14/(k14 + k10*(1 + k15/k11))*k1 - k9*k14/(k14 + k10*(1 + k15/k11))*k13))/2 + (-1)*k12*x2/k2*x3/k3*k9*k1)/k12,
  diff(x3, t) = ((-2)*k12*(k9*k14/(k14 + k10*(1 + k15/k11))*k1 + k9*k14/(k14 + k10*(1 + k15/k11))*k13 - abs(k9*k14/(k14 + k10*(1 + k15/k11))*k1 - k9*k14/(k14 + k10*(1 + k15/k11))*k13))/2 + (-2)*k12*21/100*k15/k11/(k14/k10)*(k9*k14/(k14 + k10*(1 + k15/k11))*k1 + k9*k14/(k14 + k10*(1 + k15/k11))*k13 - abs(k9*k14/(k14 + k10*(1 + k15/k11))*k1 - k9*k14/(k14 + k10*(1 + k15/k11))*k13))/2 + 1*k12*(abs(1/2*(1 - k4)*k5 + 467) - abs(1/2*(1 - k4)*k5 - 467))/2/65/2*x6/k3)/k12,
  diff(x4, t) = 0,
  diff(x5, t) = 0 }