Matrix in Latex

Question

I am new to Latex, and I have been trying to get the matrix of following form

    [x11 x12 x13 . . . . x1n
     x21 x22 x23 . . . . x2n
     .
     .
     .
     .
     xd1 xd2 xd3 . . . . xdn]

Where the letters accompanying the elements are subscripts '11 12 13' etc. I tried it in the following fashion

    $$
    \begin{bmatrix} 
    x_{11}&x_{12}&x_{13}&.&.&.&.&x_{1n}

And so on in similar fashion. I get errors when I use the above method and I know its amateurish. Can you please tell me how to get it done the right way? I even tried including '\' for the periods. Thanks in advance.

Answer 1

You must read at least lshort (page 58) or amsldoc.pdf Section 4 (page 12).

\documentclass{article}
\usepackage{amsmath}
\begin{document}
\[
\begin{bmatrix}
    x_{11}       & x_{12} & x_{13} & \dots & x_{1n} \\
    x_{21}       & x_{22} & x_{23} & \dots & x_{2n} \\
    \hdotsfor{5} \\
    x_{d1}       & x_{d2} & x_{d3} & \dots & x_{dn}
\end{bmatrix}
=
\begin{bmatrix}
    x_{11} & x_{12} & x_{13} & \dots  & x_{1n} \\
    x_{21} & x_{22} & x_{23} & \dots  & x_{2n} \\
    \vdots & \vdots & \vdots & \ddots & \vdots \\
    x_{d1} & x_{d2} & x_{d3} & \dots  & x_{dn}
\end{bmatrix}
\]
\end{document}

Answer 2

From the link @TobyStack gave:

I don't use the document/array package because I'm not very experienced.

new row:\\ (btw, you can use that for $\displaystyle\sum_{j=0\\j\ne i}^m\sum_{i=0}^n$) output:

new column: &

Also, use

    line:     \ldots 
    diagonal: \ddots 
    vertical: \vdots

output:

Depending on your preference:

    brackets: \begin{bmatrix}\end{bmatrix}
    parentheses: \begin{pmatrix}\end{pmatrix}

Screenshoot: