Hi, does anyone know how to do the following questions?

In each of the following cases, find all roots of f(x) in F and factor f(x) as the product of irreducible polynomials in F[x].

(a) F=R, f(x) = (x^6)-1 in R[x]

(b) F=Z3, f(x) = (x^5)+x+1 in Z3[x]

(c) F=Z5, f(x) = (x^3)+2x+3 in Z5[x]

Thanks very much guys....