TeX Quellcode:

\begin{array}{rclll} f''(x) &=& \dfrac{-3x^4-576}{\left(x^3-24x\right)^2} \cr\cr f''\left(-\sqrt{8}\right) &=& \dfrac{-3\cdot\left(-\sqrt{8}\right)^4-576}{\left(\left(-\sqrt{8}\right)^3-24\cdot\left(-\sqrt{8}\right)\right)^2} \quad = \quad -\dfrac{3}{8} \quad < \quad 0 & & \Rightarrow \text{Hochpunkt}\end{array}