[tex]\left[\begin{array}{ccc}2&4\\10&6\end{array}\right] +2*\left[\begin{array}{ccc}1&2\\5&3\end{array}\right] =\left[\begin{array}{ccc}2&4\\10&6\end{array}\right] -\left[\begin{array}{ccc}2&4\\10&6\end{array}\right] =\left[\begin{array}{ccc}0&0\\0&0\end{array}\right] =O2[/tex]