TeX source:
\begin{array}{lrclcll}& \mathbb{D} &=& \mathbb{R} \\\\& \dfrac{1}{4}x^3+x^2+x &=& 0 \\& x\cdot\left(\dfrac{1}{4}x^2+x+1\right) &=& 0 &\vert & \text{Satz vom Nullprodukt} \\\text{Faktor 1:} & x_1 &=& 0 \\\\\text{Faktor 2:} & \dfrac{1}{4}x^2+x+1 &=& 0 &\vert & :\dfrac{1}{4} \\& x^2+4x+4 &=& 0 &\vert & \text{p-q-Formel} \\& x_{2,3} &=& -2\pm\sqrt{2^2-4} \\& x_{2,3} &=& -2\pm\sqrt{0} \\& x_{2,3} &=& -2 \\\\& \mathbb{L} &=& \left\{0;-2\right\}\end{array}