P(x)=x^3−x^2−18x+k For the given polynomials find the sum of the squares of the roots.

Answer 1

x^3 -x^2 -18x +k has 3 roots

use one of the cubic formulas

C = cube root of ((d+/- sqr(d^2 +4f^3))/2) where d= b^2 -3ac, f = 2b^3-9abc +27a^2d

and a=1, b=-1, c=-18, e = k

for

ax^3 +bx^2 +cx + e

plug in the values and solve for C= the roots of the cubic polynomial