The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -1.563\\[1 em]x_2 &= -0.0621+0.7937i\\[1 em]x_3 &= -0.0621-0.7937i\\[1 em]x_4 &= 0.8436+1.1433i\\[1 em]x_5 &= 0.8436-1.1433i \end{aligned} $$Polynomial $ x^5+3x^2+2 $ has no rational roots that can be found using Rational Root Test, so the roots were found using Newton method.