Express (u+2)^3 + 5/u^4 in partial fractions

Answer 1

assuming the usual carelessness with parentheses,

((u+2)^3 + 5)/u^4 = (u^3 + 6u^2 + 12u + 13)/u^4 =
Now you want to find A,B,C,D such that
(u^3 + 6u^2 + 12u + 13)/u^4 = A/u + B/u^2 + C/u^3 + D/u^4
= Au^3 + Bu^2 + Cu + D = u^3 + 6u^2 + 12u + 13
I guess it's pretty obvious what that is, eh?