The roots of polynomial $ p(c) $ are:
$$ \begin{aligned}c_1 &= 2.5774\\[1 em]c_2 &= 1.4226 \end{aligned} $$The solutions of $ 3c^2-12c+11 = 0 $ are: $ c = 2-\dfrac{\sqrt{ 3 }}{ 3 } ~ \text{and} ~ c = 2+\dfrac{\sqrt{ 3 }}{ 3 }$.
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