The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0.1542\\[1 em]x_2 &= 2.3419\\[1 em]x_3 &= 0.752+0.9053i\\[1 em]x_4 &= 0.752-0.9053i \end{aligned} $$Polynomial $ 6x^4-24x^3+33x^2-24x+3 $ has no rational roots that can be found using Rational Root Test, so the roots were found using quartic formulas.