$$\left. \begin{array} { l } { x ^ { 3 } + x ^ { 2 } + x + 1 } \\ { x ^ { 4 } + 3 x ^ { 3 } + 3 x ^ { 2 } + x + 1 } \end{array} \right.$$
$\left(x+1\right)\left(x^{2}+1\right)\left(x^{4}+3x^{3}+3x^{2}+x+1\right)$
$\left(x+1\right)\left(x^{2}+1\right),\ x^{4}+3x^{3}+3x^{2}+x+1$
