The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0.2153\\[1 em]x_2 &= -1.5486 \end{aligned} $$The solutions of $ -3x^2-4x+1 = 0 $ are: $ x = -\dfrac{ 2 }{ 3 }-\dfrac{\sqrt{ 7 }}{ 3 } ~ \text{and} ~ x = -\dfrac{ 2 }{ 3 }+\dfrac{\sqrt{ 7 }}{ 3 }$.
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