The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 0.5936\\[1 em]x_2 &= -0.0936 \end{aligned} $$The solutions of $ 18x^2-9x-1 = 0 $ are: $ x = \dfrac{ 1 }{ 4 }-\dfrac{\sqrt{ 17 }}{ 12 } ~ \text{and} ~ x = \dfrac{ 1 }{ 4 }+\dfrac{\sqrt{ 17 }}{ 12 }$.
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