TeX Quellcode:

\begin{array}{rclcll}\dfrac{1}{2}\log_5\left(\dfrac{x}{4}+1\right) &=& \dfrac{1}{4} &\vert & :\dfrac{1}{2} \\\\\log_5\left(\dfrac{x}{4}+1\right) &=& \dfrac{1}{2} &\vert& 5^{*} \\\\5^{\log_5\left(\dfrac{x}{4}+1\right)} &=& 5^{\frac{1}{2}} \\\\\dfrac{x}{4}+1 &=& \sqrt{5} &\vert& -1 \\\dfrac{x}{4} &=& \sqrt{5}-1 &\vert& \cdot 4 \\x &=& 4\sqrt{5}-4 \approx 4{,}94 \;\in\;\mathbb{D} \\\\\mathbb{L} &=& \left\{4\sqrt{5}-4\right\}\end{array}