\documentclass{amsart}

\newcommand{\pathtotrunk}{../../}

% \input{\pathtotrunk text/article_preamble.tex}

\pagestyle{empty}

\begin{document}

\thispagestyle{empty}

\begin{align*}

abc bca cab ab bc ca a b c \\

x y z A u_x u_y u_z

\end{align*}

\end{document}