Dot's in center of a matrix?

Question

I'm trying to put vertical dots into a matrix, and I can only get it to align with one of the elements - as shown in:

    $$ \begin{pmatrix} 1 & -1 & 0 & 0 & \hdots & 0\\
    0 & 1 & -1 & 0 & \hdots & 0\\
    &  &  & \vdots &          \\
    0 & \hdots & 1 & -1 & 0 & 0
    \end{pmatrix} 
    $$

I was wondering if there was a way to centering the dots? I reviewed "Centering \vdots in a sparse matrix with an even number of rows" but unfortunately couldn't implement the solution.

Any help would be much appreciated.

Answer 1

Like this?

\documentclass[margin=3mm,preview]{standalone}
\usepackage{amsmath, amsfonts, amssymb}

\begin{document}
\[ 
    \begin{pmatrix} 
1 & -1      &  0 & 0    & \dotsm & 0\\
0 &  1      & -1 & 0    & \dotsm & 0\\
\multicolumn{6}{c}{$\vdots$}     \\
0 & \dotsm  &  1 & -1   & 0      & 0
    \end{pmatrix} 
\]
\end{document}