Solution
= Solution
The <factor theorem> supplies the factor $x-3$. <Polynomial division> gives
$$
x^3-x^2-8x+6=(x-3)(x^2+2x-2).
$$
The <quadratic formula> then gives the other two <roots of a polynomial>:
$$
\boxed{x=-1+\sqrt3,\quad x=-1-\sqrt3.}
$$