TeX Quellcode:

\genfrac{}{}{1pt}{0}{\frac{5}{4}}{-\frac{21}{52}} = \dfrac{5}{4} : \left(-\dfrac{21}{52}\right) = \dfrac{5}{4} \cdot \left(-\dfrac{52}{21}\right) = \dfrac{5}{1} \cdot \left( -\dfrac{13}{21} \right) = -\dfrac{65}{21}