%This command provides the text about matrix in the first part %of the column 2 of the page 4. % %The macro has one parameter % 1) The width allowed for the text \newcommand\TFourMatrix[1]{% \parbox[t]{#1}{% \DisplaySpace{\TFourDisplaySpace}{\TFourDisplayShortSpace} %The column is narrow, text looks better ragged right \raggedright \TFourTitle{Multiplication:} \begin{DisplayFormulae}{1}{0pt}{3ex plus 1ex minus .5ex}{\SmallChar}{\StyleWithoutNumber} \Fm{C = A \cdot B}, \Fm{c_{i,j} = \sum_{k=1}^n a_{i,k} b_{k,j}}. \end{DisplayFormulae} \TFourTitle{Determinants:} $\det A \neq 0$ iff $A$ is non-singular. \begin{DisplayFormulae}{1}{0pt}{3ex plus 1ex minus .5ex}{\SmallChar}{\StyleWithoutNumber} \Fm{\det A \cdot B = \det A \cdot \det B}, \Fm{\det A = \sum_\pi \prod_{i=1}^n \sign(\pi) a_{i,\pi(i)}}. \end{DisplayFormulae} \TFourTitle{$2 \times 2$ and $3 \times 3$ determinant:} \AdjustSpace{1ex plus .5ex minus .2ex} \begin{DisplayFormulae}{1}{0pt}{5ex plus 1ex minus 1ex}{\SmallChar}{\StyleWithoutNumber} \Fm{\begin{bmatrix} a &b \\ c &d \\ \end{bmatrix} = a d - b c} %Second Equation, matrix 3x3 \def\FirstPart{A=\begin{bmatrix}% a &b &c \\ d &e &f \\ g &h &i \\ \end{bmatrix}} \FmPartA{\FirstPart = g\begin{bmatrix}% b &c \\ e &f \\ \end{bmatrix} -h \begin{bmatrix}% a &c \\ d &f \\ \end{bmatrix}+} \FmPartB{\FirstPart =}{\enspace i \begin{bmatrix}% a &b \\ d &e \\ \end{bmatrix}} \Fm{\det A=a e i + b f g + c d h -c e g - f h a - i b d} \end{DisplayFormulae} \TFourTitle{Permanents:} \begin{DisplayFormulae}{1}{0pt}{3ex plus 1ex minus .5ex}{\SmallChar}{\StyleWithoutNumber} \Fm{\perm A = \sum_\pi \prod_{i=1}^n a_{i,\pi(i)}}. \end{DisplayFormulae} }% }