The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -1+\frac{\sqrt{ 42 }}{ 6 }i\\[1 em]x_2 &= -1- \frac{\sqrt{ 42 }}{ 6 }i \end{aligned} $$The solutions of $ -6x^2-12x-13 = 0 $ are: $ x = -1+\dfrac{\sqrt{ 42 }}{ 6 }i ~ \text{and} ~ x = -1-\dfrac{\sqrt{ 42 }}{ 6 }i$.
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