- TeX source:
- \begin{array}{rclcl}u^2+u-72 &=& 0 &\vert& \text{p-q-Formel} \cr u_{1,2} &=& -\dfrac{1}{2}\pm\sqrt{\left(\dfrac{1}{2}\right)^2-(-72)} \cr &=& -\dfrac{1}{2}\pm\sqrt{\dfrac{289}{4}} \cr \cr u_1 &=& -\dfrac{1}{2}+\dfrac{17}{2} = 8 \cr u_2 &=& -\dfrac{1}{2}-\dfrac{17}{2} = -9\end{array}