The roots of polynomial $ p(z) $ are:
$$ \begin{aligned}z_1 &= 1+\sqrt{ 3 }i\\[1 em]z_2 &= 1-\sqrt{ 3 }i \end{aligned} $$The solutions of $ z^2-2z+4 = 0 $ are: $ z = 1+\sqrt{ 3 }i ~ \text{and} ~ z = 1-\sqrt{ 3 }i$.
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