Is it possible to place a matrix in a Section Heading?  This is my current attempt:  \section{Analyze the invertible $M= \left[ \begin{array}{rr}2 &amp; 6 \\ 2 &amp; 4 \end{array} \right]$ matrix by doing the following:}   I want it to read:   Any help is appreciated as I am new.
123640
I was trying to insert matrix into a \subsection{}:  \subsection{Suppose $X= \begin{array}{cc} 1 &amp; 2 \\ 3 &amp; 4 \end{array}$}   This gives me an error:   ! TeX capacity exceeded, sorry [input stack size=5000].   What is wrong here? Thanks!
35438
I have the following code:  \documentclass{article} \begin{document} $ M = \bordermatrix{~ &amp; x &amp; y \cr               A &amp; 1 &amp; 0 \cr               B &amp; 0 &amp; 1 \cr} $ \end{document}   But this code makes a matrix with () and i would like it to be with [] How do i do this?
58488
When I first learned linear algebra, both the professor and the book used brackets like [ and ] to enclose matrices. However, in my current differential equations textbook, matrices are enclosed by parenthesis, and I suddenly realize everybody else are using them too.  So are brackets/parenthesis for enclosing matrices always totally interchangeable?
2524
I would like to put an underbrace below the matrix like this:  $$\left(\underbrace{ \left[\begin{array}{ccc}     a&amp;b&amp;c\\     d&amp;e&amp;f\\     g&amp;h&amp;i \end{array}\right]}_{A} \left[\begin{array}{c}     x_1\\     x_2\\     x_3 \end{array}\right]\right)$$     But I don't want the outer brackets \left( and \right) to stretch vertically. I want them to remain as if there was no underbrace. How to achieve that behaviour?
101020
I would like to sort a matrix according to a particular column. There is a sort function, but it sorts all columns independently.  For example, if my matrix data is:   1     3  5     7 -1     4   Then the desired output (sorting by the first column) would be:  -1     4  1     3  5     7   But the output of sort(data) is:  -1     3  1     4  5     7   How can I sort this matrix by the first column?
27320
I have a matrix and need to highlight some elements in the matrix. I have found how to highlight a single element (I want to put the cell in the square):  $$ A = \begin{bmatrix} \fbox{0} &amp; \fbox{0} &amp; 0 \\  \fbox{0} &amp; \fbox{0} &amp; 0 \\ 1 &amp; 1 &amp; 1 \\  \end{bmatrix}$$   But how can I outline elements of the submatrix like in the picture below? I need just a frame where some elements are located.
56051
I would like to know how to add dash lines in Matrix (see figuge)  Cheers  S.L.    \documentclass{article} \usepackage{amsmath}  \begin{document} \begin{equation} \begin{bmatrix} N &amp; B_i \\ B_i^T &amp; 0 \end{bmatrix} \begin{bmatrix} x_i\\ k \end{bmatrix} =\begin{bmatrix} n\\ 0 \end{bmatrix} \text{ with } n = A^TPl \end{equation} \end{document}
23791
How do we add a matrix to a LaTeX document?
77835
I created the following matrix with , and I would like to add at the bottom (respectively right) something like an underbrace (resp. "rightbrace") under each of the two blocks, together with a number specifying the number of columns (resp. rows) of the block. This amounts to two braces on the bottom and two on the right, and each brace should have a number below (resp. at the right) of it.  I did not find anything about that on the easybmat manual. I think I see how to do the braces with the  package, but then I am not able to create the block structure of the matrix in the first place.  \documentclass{article} \usepackage{easybmat} \begin{document} \[  M(z)= \left[ \begin{BMAT}[5pt]{c|c}{c} \begin{BMAT}[5pt]{c:c:c}{ccccccc} &amp; &amp; \\ &amp; &amp; \\ &amp; &amp; \\ v_1 &amp; \dots &amp; v_m \\ &amp; &amp; \\ &amp; &amp; \\ &amp; &amp; \end{BMAT} &amp; \begin{BMAT}{c}{c|c} \begin{BMAT}[5pt]{c:c:c}{ccc} &amp; &amp; \\ w_1(a) &amp; \dots &amp; w_n(a) \\ &amp; &amp; \end{BMAT} \\ \begin{BMAT}[10pt]{c}{c} B(z) \end{BMAT} \end{BMAT} \end{BMAT}  \right] \] \end{document}     This is more or less what i wish:
115054
$$\begin{align}\mathrm D &amp;= \left|\begin{matrix} (b+c)^2 &amp; a^2 &amp; a^2 \\ b^2 &amp; (a+c)^2 &amp; b^2 \\ c^2 &amp; c^2 &amp; (a+b)^2 \end{matrix}\right|\\ &amp;= (a+b+c)\left|\begin{matrix} b+c - a &amp; a^2 &amp; a^2 \\ b - a -c &amp; (a+c)^2 &amp; b^2 \\ 0 &amp; c^2 &amp; (a+b)^2 \end{matrix}\right| \\ &amp;= (a+b+c)^2\left|\begin{matrix} b+c - a &amp; 0 &amp; a^2 \\ b - a -c &amp; a+c - b &amp; b^2 \\ 0 &amp; c - a-b &amp; (a+b)^2 \end{matrix}\right|\\ &amp;= (a+b+c)^2\left|\begin{matrix} b+c - a &amp; 0 &amp; a^2 \\ 0 &amp; a+c - b &amp; b^2 \\ c - a-b &amp; c - a-b &amp; (a+b)^2 \end{matrix}\right|\end{align}$$  Can $\rm D$ be further simplified without expanding ?  I feel it should be because this was competition question.
118513
I have matrices for my syllabus but I don't know where they find their use. I even asked my teacher but she also has no answer. Can anyone please tell me where they are used? And please also give me an example of how they are used?
25136
I am new to Latex ;) I split my equation like this:  \begin{equation} \begin{split}     \tilde{m}=P\tilde{M} \\     \quad = K(R^1R^2R^3t) \begin{pmatrix} X \\ Y \\ 0 \\ 1 \end{pmatrix} \\     \quad= K(R^1R^2t)\begin{pmatrix} X \\ Y \\ 1 \end{pmatrix} \\     \quad= H \begin{pmatrix} X \\ Y \\ 1 \end{pmatrix}  \end{split} \end{equation}   which gives me this:   but, actually, I want it to be aligned like this:   How do I align them so it looks like the right side is always aligned?  Thanks
97662
Simple question here: how to make section headings invisible, but still get the correct list of sections in the TOC and headers ? e.g. on page 10, if I do a \section{New section}, I must not see the text "X. New section", but I still want the section to be in the TOC and in the \rightmark of the following pages, until a new section of course.  I'm using a minimalistic document (class article, with no package that are used to adjust section headings style)
115208
I'm looking for advise about handling sections a a special way. What I want:   Sections should not be numbered, they should be listed in the TOC and be available in the page header, and they should have not left indention.   A very much abridged version of what I'm currently trying is this:  \documentclass{book}  % No section numbers. \renewcommand{\thesection}{}  \begin{document}  \tableofcontents  \chapter{Foo}  % This section should be in the TOC and the page header. \section{Bar}  Lorem ipsum dolor sit amet, consetetur sadipscing elitr, sed diam nonumy eirmod tempor invidunt ut labore et dolore magna aliquyam erat, sed diam voluptua.   \end{document}   Unfortunately this does not produce the desired result. 1. and 2 work but 3. doesn't: the section titles have a left indention in the text.  How can I make all three requirenments work at the same time?
94030
I f $$A= \begin{pmatrix}1&amp; 0 &amp; 0 \\  1 &amp; 0 &amp; 1\\ 0 &amp; 1 &amp; 0 \end{pmatrix}$$  then $ A^{50} $  is   $$ \begin{pmatrix}1&amp; 0 &amp; 0 \\  50 &amp; 1 &amp; 0\\ 50 &amp; 0 &amp; 1 \end{pmatrix}$$ $$\begin{pmatrix}1&amp; 0 &amp; 0 \\  48 &amp; 1 &amp; 0\\ 48 &amp; 0 &amp; 1 \end{pmatrix}$$ $$\begin{pmatrix}1&amp; 0 &amp; 0 \\  25 &amp; 1 &amp; 0\\ 25 &amp; 0 &amp; 1 \end{pmatrix}$$ $$\begin{pmatrix}1&amp; 0 &amp; 0 \\  24 &amp; 1 &amp; 0\\ 24 &amp; 0 &amp; 1\end{pmatrix}$$   I am stuck on this problem. Can anyone help me please...............
94182
If I have a matrix of the form $$\begin{pmatrix} A &amp; -B \\ B &amp; A \end{pmatrix}$$ where all blocks are square and have the same dimensions, how do I turn it into something like $$\begin{pmatrix} X &amp; Y \\ 0 &amp; Z \end{pmatrix}$$ so that the determinant is easy to calculate using row and column operations?
95145
Is there an intelligent way to label (or name) columns in a matrix? I would like to have something like  \[M=\left[\begin{array}{c|cc} 1 &amp; 2 &amp; 3\\ 4 &amp; 5 &amp; 6 \end{array}\right],N=\left[\begin{array}{c|cc} 7 &amp; 8 &amp; 9\\ 10 &amp; 11 &amp; 12 \end{array}\right]\] \[A \ B \ C \ D \ E \ F\]   where A, B,..., F are the labels (or rather names) of the first, second, ..., sixth columns, respectively. What I want is to label A be exactly below the first column, label B be below the second column, etc., of course, nicely aligned. So far I have forced some extra spaces before the labels manually, and also experimented with the \phantom command.