Help me please with the following problem.
I want to write the following equation
$$\phi(U)_{\substack{\cap\\ \mathbb{R}}}$$
and my problem is \cap and \mathbb{R} don't appear under \phi.
How can I do?
[Tex/LaTex] problem with substack command
math-mode
Related Solutions
\substack is a modified array definition using smaller fonts so you can use a full array (as in the second example) but it's hard to read and I'd consider a different layout as in the third example where the condition is pulled out of the display. multi-letter identifiers such as homomorphism should never be set in math italic.
\documentclass{article}
\usepackage{amsmath}
\begin{document}
\[\mathcal{I}(A,B) = \inf_{\substack{h : M\times I\rightarrow M\\
h(\cdot,t) \;\text{homeomorphism}\\
h(x,0) = x\;\forall\; x\in X\\
h(A,1) = B
}} \max_{x\in X} \text{len} \;h(x, \cdot)\]
\[\mathcal{I}(A,B) = \inf_{\begin{array}{@{}c@{}}h : M\times I\rightarrow M\\
h(\cdot,t) \;\text{homeomorphism}\\
h(x,0) = x\;\forall\; x\in X\\
h(A,1) = B
\end{array}} \max_{x\in X} \text{len} \;h(x, \cdot)\]
\[\mathcal{I}(A,B) = \inf_{h} \max_{x\in X} \text{len} \;h(x, \cdot)\]
where $h$ satisfies:\\
$h : M\times I\rightarrow M$,
$h(\cdot,t) \;\text{homeomorphism}$,
$h(x,0) = x\;\forall\; x\in X$,
$h(A,1) = B$
\end{document}
You can use \mathop to "define" a math operator that allows stacking of super-/subscripts inside a display:
\documentclass{article}
\usepackage{amsmath}% http://ctan.org/pkg/amsmath
\begin{document}
\begin{equation}
\sum\limits_{i=1}^{I}\sum\limits_{i'=1}^{I}a_{ii'} + \sum\limits_{i=1}^{I}b_{i}
\end{equation}
\begin{equation}
\substack{\sum\limits_{i=1}^{I}\sum\limits_{i'=1}^{I}\\i'\neq i}a_{ii'} + \sum\limits_{i=1}^{I}b_{i}
\end{equation}
\begin{equation}
\begin{array}{@{}c@{}}\sum\limits_{i=1}^{I}\sum\limits_{i'=1}^{I}\\i'\neq i \end{array}a_{ii'}+ \sum\limits_{i=1}^{I}b_{i}
\end{equation}
\begin{equation}
\mathop{\sum_{i = 1}^I \sum_{i' = 1}^I}_{i' \neq i} a_{ii'} + \sum_{i = 1}^I b_{i}
\end{equation}
\end{document}
Best Answer
I can't tell if the items
\capand\mathbb{R}are supposed be typeset next to each other or one above the other. I suppose you may want one of the following two possibilities:The
\mathclapinstruction lets its argument "protrude" to the left and right of\phiwithout introducing unnecessary whitespace on either side.Incidentally, don't use
$$in a LaTeX document; use\[and\]instead.