TeX джерело:
{\;\;\left|\begin{array}{ccc}a_{11}&a_{12}&a_{13}\\a_{21}&a_{22}&a_{23}\\ a_{31}&a_{32}&a_{33} \end{array}\right|=\left|\begin{array}{ccc}a_{11}&a_{21}&a_{31}\\a_{12}&a_{22}&a_{32}\\ a_{13}&a_{23}&a_{33} \end{array}\right|}