Not sure if there's a better way, I haven't done polynomials
i) is quite simple, -b/a and c/a
ii) You create a quadratic equation with roots a^10 and b^10
Let u=x^(1/5), solve via quadratic formula. You will get 2 complex roots. Add them(i.e. a^10 + b^10) and then use de-moivres theorem