# Need help with enumerated list with display math

I have an enumerated list from a Proposition and would like to put this into display math style (so the subscripts on the union and intersection symbols are below not beside those symbols) and keep the numbering to the left. Here is what I currently have:

\documentclass[12pt,a4paper,oneside]{report}
\usepackage[left=2.00cm,right=2.00cm,top=2.45cm,bottom=2.5cm]{geometry}
\usepackage{amsmath,amssymb,amscd,amstext}
\usepackage{color,epsfig,fancyhdr,fleqn,latexsym,multicols,slashed}
\usepackage[thmmarks]{ntheorem}
\usepackage{tikz, subfigure}
\usepackage{verbatim}

\theoremstyle{marginbreak}
\theoremsymbol{\ensuremath{\diamondsuit}}
\theoremseparator{:}
\newtheorem{Proposition}{Proposition}

\begin{document}
\begin{Proposition}
Let $\mathcal{A} \eqdef \{A_{\alpha}|\alpha \in \Delta\}$ be an indexed family of sets. Then
\begin{enumerate}
\item $\bigcap_{\alpha \in \Delta} \, A_\alpha \subseteq A_{\beta}$ for each $\beta \in \Delta.$
\item $A_\beta \subseteq \bigcup_{\alpha \in \Delta} \, A_{\alpha}$ for each $\beta \in \Delta.$
\end{enumerate}
\end{Proposition}
\end{document}


Thanks.

-

You can use \limits, but this might produce (depending on the surrounding text) an inconsistent line spacing:

\documentclass[12pt,a4paper,oneside]{report}
\usepackage[left=2.00cm,right=2.00cm,top=2.45cm,bottom=2.5cm]{geometry}
\usepackage{amsmath,amssymb,amscd,amstext}
\usepackage{color,epsfig,fancyhdr,fleqn,latexsym,multicol,slashed}
\usepackage[thmmarks]{ntheorem}
\usepackage{tikz, subfigure}
\usepackage{verbatim}

\newcommand\eqdef{=}

\theoremstyle{marginbreak}
\theoremsymbol{\ensuremath{\diamondsuit}}
\theoremseparator{:}
\newtheorem{Proposition}{Proposition}

\begin{document}
\begin{Proposition}
Let $\mathcal{A} \eqdef \{A_{\alpha}|\alpha \in \Delta\}$ be an indexed family of sets. Then
\begin{enumerate}
\item $\bigcap\limits_{\alpha \in \Delta} \, A_\alpha \subseteq A_{\beta}$ for each $\beta \in \Delta.$
\item $A_\beta\subseteq \bigcup\limits_{\alpha \in \Delta} \, A_{\alpha}$ for each $\beta \in \Delta.$
\end{enumerate}
\end{Proposition}
\end{document}


I used a "fake" definition of \eqdef since you didn't provided it in your example code. By the way, the package is multicol and not multicols; fix that in your preamble.

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Thanks that helps, but i really would like (in addition to the formatting above in your 'display') for the - \alpha \in \Delta - to be underneath the intersection and union symbols respectively. – Michael Dykes May 16 '12 at 18:14
@MichaelDykes well, my example shows that now the limits are underneath, so I don't understand your comment. Please elaborate. – Gonzalo Medina May 16 '12 at 18:19
OK, I am mistaken - that works out fine. One more question (if I may) - is there an easy way to make the union and intersection symbols larger - i.e. the size they would be if used by themselves in a display math environment? Thanks. – Michael Dykes May 16 '12 at 18:22
@MichaelDykes: you can use \displaystyle\bigcap, and \displaystyle\bigcup. But I would rather suggest you to use the standard in-line math settings; of course, this is just a suggestion ;-) – Gonzalo Medina May 16 '12 at 18:24
OK Thanks again :) – Michael Dykes May 16 '12 at 18:28