The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= \frac{\sqrt{ 195 }}{ 15 }\\[1 em]x_2 &= - \frac{\sqrt{ 195 }}{ 15 } \end{aligned} $$The solutions of $ 15x^2-13 = 0 $ are: $ x = - \dfrac{\sqrt{ 195 }}{ 15 } ~ \text{and} ~ x = \dfrac{\sqrt{ 195 }}{ 15 }$.
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