How to get this side by side?

Question

I have the following code:

$ax = b \Leftrightarrow$

and

\begin{tabbing}
    $a_{11}x_1 + $ \= $a_{12}x_2+\dots +$ \= $a_{1n}x_n$ \= $= b_1$\\
    \> $a_{22}x_2 + \dots +$ \> $a_{2n}x_n$ \> $= b_2$\\
    \> $\ddots$ \> $\vdots$ \> $\vdots$\\
    \> \> $a_{nn}x_n$ \> $= b_n,$
\end{tabbing}

But how can I get, that these two parts are side by side?

Thank you very much!

Do you know the environments align and array? Maybe you should read the mathmode. — Marco Daniel, Dec 19 '13 at 13:40
And a link to math-mode as suggested my @MarcoDaniel Just to get you on the right track ;-) — Johannes_B, Dec 19 '13 at 13:59

karlkoeller · Answer 1 · 2017-05-27T08:29:48.383

4

I would follow the suggestions in the above comments, but just in case you don't want to change your code, you can exploit minipage. Inserting a tabbing inside it causes the minipage to use the width of the tabbing, as egreg suggested in his comments.

MWE

\documentclass{article}

\begin{document}

$ax = b \quad\Leftrightarrow\quad$
\begin{minipage}{\linewidth}
\begin{tabbing}
    $a_{11}x_1 + $ \= $a_{12}x_2+\dots +$ \= $a_{1n}x_n$ \= $= b_1$\\
    \> $a_{22}x_2 + \dots +$ \> $a_{2n}x_n$ \> $= b_2$\\
    \> $\ddots$ \> $\vdots$ \> $\vdots$\\
    \> \> $a_{nn}x_n$ \> $= b_n,$
\end{tabbing}
\end{minipage}

\end{document}

Output

enter image description here

The same result can be achieved using the varwidth environment from the same package.

MWE

\documentclass{article}

\usepackage{varwidth}

\begin{document}

$ax = b \quad\Leftrightarrow\quad$
\begin{varwidth}{\linewidth}
\begin{tabbing}
    $a_{11}x_1 + $ \= $a_{12}x_2+\dots +$ \= $a_{1n}x_n$ \= $= b_1$\\
    \> $a_{22}x_2 + \dots +$ \> $a_{2n}x_n$ \> $= b_2$\\
    \> $\ddots$ \> $\vdots$ \> $\vdots$\\
    \> \> $a_{nn}x_n$ \> $= b_n,$
\end{tabbing}
\end{varwidth}

\end{document}

edited May 27 '17 at 08:29

answered Dec 19 '13 at 15:36

karlkoeller

124,410

There's no need of varwidth; try \begin{minipage}{\linewidth} instead and you'll get the same result. A minipage that only contains a tabbing uses the width of the tabbing (unless it's wider than the stated minipage width). Also the first varwidth you use is redundant. – egreg Dec 19 '13 at 17:57
@egreg Is this true for the first varwidth? – karlkoeller Dec 19 '13 at 17:59
Why would you need it? – egreg Dec 19 '13 at 18:14
@egreg Stupid me, you're right... – karlkoeller Dec 19 '13 at 18:18

score 4 · Accepted Answer · edited May 27 '17 at 08:25

4

A simple array can be used instead of tabbing, which also centers itself vertically with the math axis:

enter image description here

\documentclass{article}

\newcommand{\mcr}{\multicolumn{1}{r}}

\begin{document}

\[
  AX = B
  \quad\Leftrightarrow\quad
  \setlength{\arraycolsep}{0pt}% No intercolumn space in array
  \begin{array}{rccl}
    a_{11}x_1 + a_{12}x_2 & {}+ \cdots + a_{1n}x_n & {}={}  & b_1 \\
                a_{22}x_2 & {}+ \cdots + a_{2n}x_n & {}={}  & b_2 \\[\jot]
                   \ddots &      \mcr{\vdots\quad} & \vdots &     \\[\jot]
                          &        \mcr{a_{nn}x_n} & {}={}  & b_n,
  \end{array}
\]

\end{document}

edited May 27 '17 at 08:25

karlkoeller

124,410

answered Dec 19 '13 at 17:51

Werner

603,163

Werner, just in case you are interested, take a look at https://tex.meta.stackexchange.com/a/7303/27635 – karlkoeller May 27 '17 at 08:28
Thanks! This is great. I was waiting for a review queue to be established, but in the meantime it's probably best to go ahead and fix what we can. – Werner May 27 '17 at 16:11

How to get this side by side?

2 Answers2