$$-x^3+2x^2+x-1 = 0$$
Answer
$$ \begin{matrix}x_1 = 0.55496 & x_2 = -0.80194 & x_3 = 2.24698 \end{matrix} $$
Explanation
This polynomial has no rational roots that can be found using Rational Root Test.
Roots were found using qubic formulas.
This page was created using
Polynomial Equations Solver