TeX Quellcode:

\begin{array}{ccl} 10 \lg \left( \sqrt{f^2+w^2} \right) &=& 10 \lg \left( \left( f^2+w^2 \right)^\frac{1}{2} \right) \cr\cr &=& 10 \cdot \dfrac{1}{2} \cdot \lg \left( f^2+w^2 \right) \cr\cr &=& 5 \lg \left( f^2+w^2 \right) \end{array}