\begin{bmatrix}
{2 \boldsymbol A \boldsymbol{A} ^{*}} & {\boldsymbol{O}} \\
{\boldsymbol{O}} & {3 \boldsymbol B \boldsymbol B^{*}}
\end{bmatrix}=
\begin{bmatrix}
{4 \boldsymbol{E}} & {} \\
{} & {9 \boldsymbol{E}}
\end{bmatrix}
I want to draw a curve,from 2 \boldsymbol A \boldsymbol{A} ^{*} to 4 \boldsymbol{E}, it could be better if the curve can addon text/formula.how to achieve this?

