[−1301]\left[\begin{array}{rr}-1 & 3 \\0 & 1\end{array}\right][−1031]
[130−1]\left[\begin{array}{rr}1 & 3 \\0 & -1\end{array}\right][103−1]
[103−1]\left[\begin{array}{rr}1 & 0 \\3 & -1\end{array}\right][130−1]
[−10−31]\left[\begin{array}{cc}-1 & 0 \\-3 & 1\end{array}\right][−1−301]