Again I have no clue in figuring out this problem, please help:
(3s^4-3s^3+3s^2+13s-6) + (s^5+8s^3+6s^2-3s+3) +
(-6s^4+s^2-7s-6)=
Group all like-terms. Start with the highest term.
s^5+(3s^4-6s^4)+(-3s^3+8s^3)+(3s^2+6s^2+s^2) + (13s+3s-7s)+(-6+3-6)=
Combine like-terms.
s^5 - 3s^4 + 5s^3 + 10s^2 + 9s - 9.