This is LaTeX code:

[latex]
X\sim
\begin{pmatrix}
 0 & 1 & ... & m1 \\ 
 a_{0} & a_{1} & ... & a_{m1}
\end{pmatrix} Y\sim
\begin{pmatrix}
 0 & 1 & ... & m2 \\ 
 b_{0} & b_{1} & ... & b_{m2}
\end{pmatrix} 
[/latex]