Für die Vektoren $\overrightarrow{a_k}\backslash overrightarrow\{a\_k\}$, $\overrightarrow{b}\backslash overrightarrow\; b$ und $\overrightarrow{c}\backslash overrightarrow\; c$ mit $k\in \mathbb{R}k\backslash in\; \backslash mathbb\{R\}$ im ${\mathbb{R}}^{\mathbb{3}}\backslash mathbb\{R^3\}$ gilt:

$\overrightarrow{a_k}=\left(\begin{array}{c}-1\\ 0\\ 2k\end{array}\right)\backslash vec\{a\_k\}\; =\; \backslash begin\{pmatrix\}\; -1\; \backslash \backslash \; 0\; \backslash \backslash \; 2k\; \backslash end\{pmatrix\}$ und $\vec{b}\times \vec{c}=\left(\begin{array}{c}1\\ 2\\ -2\end{array}\right)\backslash vec\{b\}\backslash times\; \backslash vec\{c\}\; =\; \backslash begin\{pmatrix\}\; 1\; \backslash \backslash \; 2\; \backslash \backslash \; -2\; \backslash end\{pmatrix\}$