The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -0.8453\\[1 em]x_2 &= -3.1547 \end{aligned} $$The solutions of $ -3x^2-12x-8 = 0 $ are: $ x = -2-\dfrac{ 2 \sqrt{ 3}}{ 3 } ~ \text{and} ~ x = -2+\dfrac{ 2 \sqrt{ 3}}{ 3 }$.
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