The roots of polynomial $ p(x) $ are:
$$ \begin{aligned}x_1 &= -0.7549\\[1 em]x_2 &= 0.8774+0.7449i\\[1 em]x_3 &= 0.8774-0.7449i \end{aligned} $$Polynomial $ x^3-x^2+1 $ has no rational roots that can be found using Rational Root Test, so the roots were found using qubic formulas.