the formula sheet only has the sum and roots of cubics.
my question is whether sum and product equations of quartics and quadratic are needed?
Most likely, it will not appear however it isn't that hard to understand.
Try deriving the identity for:
suppose x^4 +a3*x^3 + a2*x^2+ a1*x +a0 = (x-a)(x-b)(x-c)(x-d).
All that is being applied is the distributive law a(b+c).
E.g., Note that for term a3*x^3, x is select three times. This means that each root can only be select once.
Similarly you could do the same thing for a2*x^2 in this case x is selected two times which means you can take the roots two at a time.
It is similar to the idea behind binomial theorem.