The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0.4392\\[1 em]x_2 &= -2.9722\\[1 em]x_3 &= 0.4628+0.3042i\\[1 em]x_4 &= 0.4628-0.3042i\\[1 em]x_5 &= -1.1964+1.0326i\\[1 em]x_6 &= -1.1964-1.0326i \end{aligned} $$Polynomial $ x^6+4x^5+3x^4-2x^3-4x^2+4x-1 $ has no rational roots that can be found using Rational Root Test, so the roots were found using Newton method.