I need to write a fraction that has the 'min operator in the denominator

Question

Here is what I have typed:

\begin{equation*}
s_j=\frac{e_j}{\min_{1 \leq k \leq m-1} \big\{t_{jk} + t_{j(k+1)} \big\}
\end{equation*}

however, it is displaying as a subscript rather than UNDER the min operator.

Is this because the operator is in the denominator?

How do I fix this?

thanks :)

Answer 1

TeX forces the scriptstyle when typesetting denominators in display math.

This way the min operator loses the limits, which are typeset in a nolimit way.

I suggest to typeset \limits as suggestd by PeterGrill:

\documentclass{article}
\usepackage{amsmath}

\begin{document}
    \begin{equation*}
    s_j=\frac{e_j}{\min\limits_{1 \leq k \leq m-1} \big\{ t_{jk} + t_{j(k+1)} \big\}}
    \end{equation*}
\end{document}

Producing:

As correctly remarked by @Thurston, you can also achieve a similar using the \displaystyle cmmand, which yields the same result here, but it's not recommended since it changes all of the group style. Anyway here it is:

\documentclass{article}
\usepackage{amsmath}

\begin{document}
    \begin{equation*}
    s_j=\frac{e_j}{\displaystyle\min_{1 \leq k \leq m-1} \big\{ t_{jk} + t_{j(k+1)} \big\}}
    \end{equation*}
\end{document}

Outputting: