# \marginpar and \begin{align}

I want to use \marginpar directly beside a formula within a \begin{align} statement. I tried:

\begin{align}
E^2
\end{align}
\marginpar{Not correct}


but the 'Not correct' statement is written besides the next line. How can I achieve that is is written besides E^2 (means on the same height)?

And what if I have more than one formula, how to achieve to write it besides the very last of the align-environment?

You could use the marginnote package and use its \marginnote command. \marginnote is a non-floating version of \marginpar and can also be used inside the align environment:

\documentclass{article}

\usepackage{amsmath}
\usepackage{marginnote}

\begin{document}

\begin{align}
E^2 \marginnote{Not correct}
\end{align}

\end{document}