The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -1.0036+0.6066i\\[1 em]x_2 &= -1.0036-0.6066i\\[1 em]x_3 &= -0.3751+1.7247i\\[1 em]x_4 &= -0.3751-1.7247i\\[1 em]x_5 &= 1.7121+0.4252i\\[1 em]x_6 &= 1.7121-0.4252i \end{aligned} $$Polynomial $ 3x^6-2x^5-x^4-14x^3-6x^2+24x+40 $ has no rational roots that can be found using Rational Root Test, so the roots were found using Newton method.