The error is missing delimiter (.inserted). \end{frame} (\documentclass{beamer})

Question

\begin{frame}
\begin{defi}
The class of symbols $\mathnormal{S^m}$ consist the set of
function $\mathnormal{ P(x,\xi)\in C^\infty(R^N\times R^N)}$  such
that for each compact set $\mathnormal {K\subset R^N}$  and 
all multi-indices
 $\alpha , \beta$ satisfying
$$\mathnormal{|D_x^\beta D_\xi^\alpha P(\xi)| \leq C_{\alpha ,\beta} (\big1+|\xi|)^{m-|\alpha|}}.$$
%where $|\alpha|=\alpha_1+\dots+\alpha_n $ , and $\mathnormal{m\in
\end{defi}
Formula (1) assigns to each symbol $\mathnormal{P(x,\xi)\in S^m}$
a pseudodifferential operator $\mathnormal{ P(x,D)}$ of order
$\mathnormal{m}.$ \newline
\textbf{Example}: The function $\mathnormal{p(\xi)=\sqrt{1+|\xi|^2}}$ is a pseudodifferential
 symbol of order 1. Where $\mathnormal{\big1+|\xi|^2}$ is the
 symbol of $1-\triangle$, and ${\triangle=\partial_{x_1}^2+\ldots +\partial_{x_n}^2}$ is Laplace operator. 
\end{frame}

Thanks in advance for any help

Welcome to TeX.SX! Please help us help you and add a minimal working example (MWE) that illustrates your problem. Reproducing the problem and finding out what the issue is will be much easier when we see compilable code, starting with \documentclass{...} and ending with \end{document}. — samcarter_is_at_topanswers.xyz, Jul 31 '17 at 23:49
And please have a look at Why is \[ … \] preferable to $$? — samcarter_is_at_topanswers.xyz, Jul 31 '17 at 23:50
The problem is with \big you are using (twice) without delimiter. — Sigur, Jul 31 '17 at 23:51
this \big tomake 1 big if i dont put or if insert . it look small. so my question how do i make it look big? — Ehab Jad, Aug 01 '17 at 00:02
I think that what you want is to use math serif fonts for beamer slides. Search for it. — Sigur, Aug 01 '17 at 00:11
@Sigur Would you like to write an answer about the missing delimiter? — samcarter_is_at_topanswers.xyz, Aug 05 '17 at 13:08

score 2 · Answer 1 · answered Aug 05 '17 at 13:24

The problem is in the command \big which you are using (twice) without delimiter as argument.

When you want to change the size of delimiters, you can use \bigl \bigr but you must give which delimiter you want. For example:

\bigl( \bigr) \bigl[ \bigr] \bigl\{ \bigr\}

No problem mixing it:

\bigl( \bigr\} \bigl( \bigr] \bigl\{ \bigr]

The error is missing delimiter (.inserted). \end{frame} (\documentclass{beamer})

1 Answers1