Well considering this code, the "E" is shown after the integral:
\begin{equation}
m = \iiint_E \rho \ \mathrm{d}V
\end{equation}
The limit is shown slightly behind the number, how can I place it in the middle below the triple integral?
You need to insert \limits
after \iiiint
:
\documentclass{article}
\usepackage{amsmath} % for \iiint macro
\begin{document}
\begin{equation}
m = \iiint\limits_E \rho \, \mathrm{d}V
\end{equation}
\end{document}
,
; instead, I put in the \,
macro, which inserts a typographic thinspace. In contrast, the \
macro in your example inserts a full interword space, which is probably more whitespace than is typographically optimal.
\;
or \thickspace
. The default values of thin-, med-, and thickspace, in both plain TeX and the LaTeX kernel, are 3mu
, 4mu
, and 5mu
, respectively. (Recall that 1em=18mu
. "Why 18mu
to the em
?", you may ask. I have no idea...) The difference between thin- and thickspace thus isn't that huge -- though certainly noticeable to the human eye.