The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0.3161\\[1 em]x_2 &= -2.3161\\[1 em]x_3 &= -1+1.3161i\\[1 em]x_4 &= -1-1.3161i \end{aligned} $$Polynomial $ x^4+4x^3+6x^2+4x-2 $ has no rational roots that can be found using Rational Root Test, so the roots were found using quartic formulas.