# minipage does not work properly

I am trying to get two sets of equations to show up in line with the text width in a minipage environment, however, I am not getting the correct output. The second minipage goes outside the textwidth. Here is my code:

\documentclass[11pt,fleqn]{book}
\usepackage{empheq}

\begin{document}
\begin{minipage}[l]{.5\textwidth}
\begin{align}
\end{align}
\end{minipage}
\begin{minipage}{0.5\textwidth}
\begin{align*}
\mbox{where}\begin{cases}
\end{cases}
\end{align*}
\end{minipage}
\end{document}


• \parindent, \mathindent (option fleqn), space between the minipages, two minipages with together \textwidth, and the legend in the second minipage is way too large for 0.5\textwidth. I suggest, you put the legend somewhere else (above, below). – Heiko Oberdiek Mar 21 '14 at 21:12
• Is it possible to shift the 1st mini page more to the left? – Joe Mar 21 '14 at 21:35
• \noindent\begin{minipage}\setlength{\mathindent}{0pt}. – Heiko Oberdiek Mar 21 '14 at 21:51

Don't use math italic for multi-letter identifiers.

If you really want this layout, you need to lose all the indentation. In your MWE the content did not fit in the minipages, and the minipages did not fit on the line (as you had \parindent to the left and and a word space between them as well as the two .5\textwidth boxes.

\documentclass[11pt,fleqn]{book}
\usepackage{empheq,amsmath}

\begin{document}
\noindent
\begin{minipage}[l]{.4\textwidth}
\setlength\mathindent{0pt}
\begin{align}
\end{align}
\end{minipage}\hfill
\begin{minipage}{0.5\textwidth}
\setlength\mathindent{0pt}
\begin{align*}
\begin{cases}
A_{1}&=\mbox{Peak VCO Phase Deviation}\\
A_{2}&=\mbox{Modulation Frequency}\\
A_{3}&=\mbox{peak VCO freq. Deviation}\\
A_{4}&=\mbox{Reference Frequency}\\
A_{5}&=\mbox{Loop Divide Ratio}
\end{cases}
\end{align*}
\end{minipage}

\hrule
\end{document}

• The &= in cases are wrong. – egreg Mar 21 '14 at 23:31
• @egreg true, I was just concentrating on the spacing (but I wouldn't use this side by side layout at all) – David Carlisle Mar 21 '14 at 23:33
• Neither would I. – egreg Mar 21 '14 at 23:34