TeX Quellcode:

\begin{array}{rclll}\sqrt{4-x}+2 &=& 4 & \vert &-2 \\\sqrt{4-x} &=& 2 &\vert & \left(\right)^2\\4-x &=& 4 &\vert & -4 \\-x &=& 0 &\vert& \cdot(-1) \\x &=& 0 \in\mathbb{D}\end{array}