# 'amsmath' option 'tbtags' not working in beamer

I would like to use the tbtags option with amsmath multiline equations in beamer. Unfortunately, I cannot get it to work. Here is a minimal example that works using article, but does not work with beamer.

\documentclass[amsmath={tbtags}]{beamer}
\begin{document}
$$\begin{split} M &= \text{first line} \\ &\qquad \text{second line} \end{split}$$
\end{document}


I can't find anything in the beamer docs indicating that this should not work. What am I doing wrong?

Using the noamsthm option, beamer does not load amsmath by default and you can load it with whatever options you like.

\documentclass[noamsthm]{beamer}

\usepackage[tbtags]{amsmath}

\begin{document}
$$\begin{split} M &= \text{first line} \\ &\qquad \text{second line} \end{split}$$
\end{document}


• That did it! Thank you! By the way, beamer does load amsmath. :-) – Gary L. Gray Jun 28 '18 at 19:52
• @GaryL.Gray Beamer only loads amsmath if the option noamsthm is not given, see user guide p. 121 – samcarter_is_at_topanswers.xyz Jun 28 '18 at 19:55

you can your write mwe correctly as follows:

\documentclass[tbtags]{beamer}

\begin{document}
\begin{frame}
$$\begin{split} M &= \text{first line} \\ &\qquad \text{second line} \end{split}$$
\end{frame}
\end{document}


• @samcarter, indeed. number is not positioned correctly. i will correct my answer accordingly asap. – Zarko Jun 28 '18 at 20:52
• The difference is really hard to see. When I first saw this questions I was wondering what the problem is because the code compiled just fine :) – samcarter_is_at_topanswers.xyz Jun 28 '18 at 21:18