The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 5.7216\\[1 em]x_2 &= 0.6117 \end{aligned} $$The solutions of $ 6x^2-38x+21 = 0 $ are: $ x = \dfrac{ 19 }{ 6 }-\dfrac{\sqrt{ 235 }}{ 6 } ~ \text{and} ~ x = \dfrac{ 19 }{ 6 }+\dfrac{\sqrt{ 235 }}{ 6 }$.
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