$$\begin{bmatrix} -3i \\ 9 \end{bmatrix}
\begin{bmatrix} 9i \\ 2 \end{bmatrix}^\dagger =
\begin{bmatrix} -3i \\ 9 \end{bmatrix}
\begin{bmatrix} -9i & 2 \end{bmatrix} =
\begin{bmatrix}
    (-3i) \cdot (-9i) & (-3i) \cdot 2 \\
    9 \cdot (-9i) & 9 \cdot 2
\end{bmatrix} =
\begin{bmatrix}
    -27 & -6i \\
    -81i & 18
\end{bmatrix}$$

@[solution]({"id": "linear_algebra__outer_product_solution", "codePath": "Solution.qs"})
