The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -1.472\\[1 em]x_2 &= 1.6194\\[1 em]x_3 &= 1.1179+1.2595i\\[1 em]x_4 &= 1.1179-1.2595i\\[1 em]x_5 &= -0.6916+1.427i\\[1 em]x_6 &= -0.6916-1.427i \end{aligned} $$Polynomial $ x^6-x^5+2x^2+3x-17 $ has no rational roots that can be found using Rational Root Test, so the roots were found using Newton method.