%% 
%%  Example 01-02-6 
%%  Copyright (C) 2017 Herbert Voss
%% 
%% ==== 
% Show page(s) 1
%% 
%% 
\documentclass[]{screxa}
\pagestyle{empty}
\setlength\textwidth{328.62788pt}
\setlength\parindent{0pt}
%StartShownPreambleCommands

%StopShownPreambleCommands
\begin{document}
foo \fbox{$ f(x)=\int_1^{\infty}\frac{1}{x^2}\,\mathrm{d}x=1 $} bar      \\
%
foo \rule{20pt}{\ht\strutbox}\fbox{$ f(x)=\int_1^{\infty}\frac{1}{x^2}\,
          \mathrm{d}x=1 $}\rule{20pt}{\ht\strutbox} bar                  \\
%
\setlength{\mathsurround}{20pt}%
foo \fbox{$ f(x)=\int_1^{\infty}\frac{1}{x^2}\,\mathrm{d}x=1 $} bar
\end{document}
