TeX source:
\begin{array}{crclll} & -256 &=& x^{16}-x^8-256 & \vert & +256 \cr & 0 &=& x^{16}-x^8 \cr & 0 &=& x^8\left(x^8-1\right) & \vert & \text{Satz vom Nullprodukt} \cr \text{Faktor 1:} & x^8 &=& 0 &\vert& \pm\sqrt[8]{}\cr & x_2 &=& 0 & & \rightarrow \quad P_2(0 \mid -256) \cr\cr \text{Faktor 2:} & x^8-1 &=& 0 & \vert & +1 \cr & x^8 &=& 1 & \vert & \pm\sqrt[8]{} \cr & x_3 &=& \sqrt[8]{1} = 1 & & \rightarrow \quad P_3(1 \mid -256) \cr & x_4 &=& -\sqrt[8]{1} =-1 & & \rightarrow \quad P_4(-1 \mid -256) \end{array}