The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -0.6592\\[1 em]x_2 &= -0.1704+1.4988i\\[1 em]x_3 &= -0.1704-1.4988i \end{aligned} $$Polynomial $ 2x^3+2x^2+5x+3 $ has no rational roots that can be found using Rational Root Test, so the roots were found using qubic formulas.