\[
A \times A^{-1} =
\begin{bmatrix}
2 & 1 & 0 \\
1 & 2 & 1 \\
0 & 1 & 2
\end{bmatrix}
\times
\begin{bmatrix}
\frac{4}{3} & -\frac{2}{3} & \frac{4}{3} \\
-\frac{2}{3} & 1 & -\frac{2}{3} \\
\frac{4}{3} & -\frac{2}{3} & \frac{4}{3}
\end{bmatrix}
\]

\[
\text{Result} =
\begin{bmatrix}
a & b & c \\
d & e & f \\
g & h & i
\end{bmatrix}
\]



a =   b =   c =

d =   e =   f =

g =   h =   i =

\[
B \times B^{-1} =
\begin{bmatrix}
4 & 2 & 1 \\
1 & 3 & 2 \\
2 & 1 & 4
\end{bmatrix}
\times
\begin{bmatrix}
\frac{4}{13} & -\frac{2}{13} & -\frac{1}{13} \\
-\frac{1}{13} & \frac{4}{13} & -\frac{2}{13} \\
-\frac{2}{13} & -\frac{1}{13} & \frac{4}{13}
\end{bmatrix}
\]

\[
\text{Result} =
\begin{bmatrix}
a & b & c \\
d & e & f \\
g & h & i
\end{bmatrix}
\]

a =   b =   c =

d =   e =   f =

g =   h =   i =