finding a particular solution in a laplace equation?

to find k1 , use method of undetermined coefficients:
lets Up = k1 where k1 is arbitrary constant

subsitute into A(d^2u/dz^2) - su = -c
you get 0-s(k1)=-c
k1=c/s

Y(y(t))(s+3)^2 - 4s - 20 = -5/(s + 8) - a million / (s + 3) So Y(y(t)) = (-5/(s+8) - a million/(s+3) + 4s + 20)/(s+3)^2. This solves area a-c, from right here this is basically a team of fraction help and then looking the inverse.