The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 2 \sqrt{ 3 }\\[1 em]x_2 &= -2 \sqrt{ 3 } \end{aligned} $$The solutions of $ 3x^2-36 = 0 $ are: $ x = -2 \sqrt{ 3 } ~ \text{and} ~ x = 2 \sqrt{ 3 }$.
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