The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= \frac{ 1 }{ 3 }\\[1 em]x_2 &= -\frac{ 1 }{ 4 } \end{aligned} $$The solutions of $ 12x^2-x-1 = 0 $ are: $ x = -\dfrac{ 1 }{ 4 } ~ \text{and} ~ x = \dfrac{ 1 }{ 3 }$.
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