The roots of polynomial $ p(k) $ are:
$$ \begin{aligned}k_1 &= -0.2324\\[1 em]k_2 &= -1.4343 \end{aligned} $$The solutions of $ 3k^2+5k+1 = 0 $ are: $ k = -\dfrac{ 5 }{ 6 }-\dfrac{\sqrt{ 13 }}{ 6 } ~ \text{and} ~ k = -\dfrac{ 5 }{ 6 }+\dfrac{\sqrt{ 13 }}{ 6 }$.
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