TeX Quellcode:

\begin{array}{rcl} A_O &=& 2(ab+ac+bc) \cr A_O &=& 2\left(ab+a\dfrac{V}{a\cdot 2a}+b\dfrac{V}{a\cdot 2a}\right) \cr A_O &=& 2 \left(4 \, cm \cdot 8 \, cm+4 \, cm \cdot \dfrac{250\, cm^3}{4 \, cm \cdot 8 \, cm}+8 \, cm \cdot \dfrac{250\, cm^3}{4 \, cm \cdot 8 \, cm} \right) \cr A_O &=& 251{,}5 \, cm^2 \end{array}