\begin{Verbatim}[commandchars=\\\{\}]
 The double angle formula can now be rewritten as
\PYG{k}{\PYGZbs{}begin}\PYG{n+nb}{\PYGZob{}}align\PYG{n+nb}{\PYGZcb{}}
    \PYG{k}{\PYGZbs{}cos}(2\PYG{k}{\PYGZbs{}theta}) \PYG{n+nb}{\PYGZam{}}=  \PYG{k}{\PYGZbs{}cos}\PYG{n+nb}{\PYGZca{}}2\PYG{k}{\PYGZbs{}theta} \PYGZhy{} sin\PYG{n+nb}{\PYGZca{}}2\PYG{k}{\PYGZbs{}theta} \PYG{k}{\PYGZbs{}\PYGZbs{}}
                  \PYG{n+nb}{\PYGZam{}}= 2\PYG{k}{\PYGZbs{}cos}\PYG{n+nb}{\PYGZca{}}2\PYG{k}{\PYGZbs{}theta} \PYGZhy{} 1
\PYG{k}{\PYGZbs{}end}\PYG{n+nb}{\PYGZob{}}align\PYG{n+nb}{\PYGZcb{}}
\end{Verbatim}