\( = (\hat i + 2\hat j + 3\hat k) \times 3\hat i - 2\hat j + \hat k)\)
\( = \left|{\,\begin{array}{*{20}{c}}{\hat i}&{\hat j}&{\hat k}\\1&2&3\\3&{ - 2}&1\end{array}\,} \right|\)
\( = (8)\hat i + (8)\hat j - (8)\hat k\)
Magnitude \( = \sqrt {64 + 64 + 64} \)=\(8\sqrt 3 \)