%%
%% The LaTeX Companion, 3ed
%%
%% Example 11-7-12 on page II-201 in "Ghostbusters\texttrademark ".
%%
%% Copyright (C) 2022 Frank Mittelbach
%%
%% It may be distributed and/or modified under the conditions
%% of the LaTeX Project Public License, either version 1.3c
%% of this license or (at your option) any later version.
%%
%% See
https://www.latex-project.org/lppl.txt for details.
%%
\documentclass{tlc3examargin}
\pagestyle{empty}
\setcounter{page}{6}
\setlength\textwidth{147.0pt}
%StartShownPreambleCommands
\usepackage{amsmath}
%StopShownPreambleCommands
\begin{document}
\[ f_p (x) =
\begin{cases}
\frac{1}{\smash[b]{p}} & x = p \\
\frac{\strut % strut added
\smash[t]{\frac{(1 - x)^{\frac{1}{2}}}
{ x - \sin (x - p) } } }
{\sqrt{1 - p} \, \cos (x - p)} & x \neq p
\end{cases} \]
\end{document}
