The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= 2.3593\\[1 em]x_2 &= -0.1797+0.903i\\[1 em]x_3 &= -0.1797-0.903i \end{aligned} $$Step 1:
Write polynomial in descending order
$$ \begin{aligned} 2x^2-x^3+2 & = 0\\[1 em] -x^3+2x^2+2 & = 0 \end{aligned} $$Step 2:
Polynomial $ -x^3+2x^2+2 $ has no rational roots that can be found using Rational Root Test, so the roots were found using qubic formulas.