[tex] A= \left[\begin{array}{ccc}a_{11}&a_{12}\\a_{21}&a_{22}\\a_{31}&a_{32}\end{array}\right] \\
\\
A=\left[\begin{array}{ccc}{2.1-1}&{2.1-2}\\{2.2-1}&{2.2-2}\\{2.3-1}&{2.3-2}\end{array}\right] \\
\\
A=\left[\begin{array}{ccc}{1}&{0}\\{3}&{2}\\{5}&{4}\end{array}\right] \\[/tex]
