TeX Quellcode:

\begin{array}{rcl} \displaystyle\int x^2 \cdot e^x \, dx &=& e^x \cdot x^2 - \displaystyle\int e^x \cdot 2x \, dx \cr\cr &=& x^2 \cdot e^x - 2 \displaystyle\int x \cdot e^x \, dx \end{array}