s*L(X) - Dose = -kel*L(X)
L(X) = Dose/(s+kel)
dM1/dt = km1*X - kmu1*M1
s*L(M1) = km1*L(X) - kmu1*L(M1)
L(M1) = km1*L(X)/(s+kmu1) = km1*Dose/(s+kel)*(s+kmu1)
dMu1/dt = kmu1*M1
s*L(Mu1) = kmu1*L(M1)
L(Mu1) = kmu1*L(M1)/s = kmu1*km1*Dose/(s*(s+kel)*(s+kmu1))
OK!!
Three roots: 0, -kel, and -kmu1
Mu1 = kmu1*km1*Dose/(kel*kmu1)
+ kmu1*km1*Dose*exp(-kel*t)/(-kel*(kmu1-kel))
+ kmu1*km1*Dose*exp(-kmu1*t)/(-kmu1*(kel-kmu1))