"no line here to end" and "missing $ inserted"

Question

at the moment I get a pretty simple tex error, but I don't know how to handle it: the following code (an excerpt of a larger thing but with the same error) gives me those three errors:

6: LaTeX Error: There's no line here to end. [\end{frame}]  
6: Missing $ inserted. [\end{frame}]  
6: Missing $ inserted. [\end{frame}]

Here is the code, I really don't know what is wrong:

\documentclass{beamer}
\begin{document}
\begin{frame}
  $\langle\alpha v_1,\beta v_2\rangle=\alpha\beta-\alpha\beta=0\\
  \langle\alpha v_1,\beta v_4\rangle=\alpha\beta-\alpha\beta=0$
\end{frame}
\end{document}

Edit: it works if I replace \\ with \newline - but shouldn't \\ also work?

Thanks in advance!

Answer 1

It's working with replacing \\ with \newline, so my problem is solved. The other option is with two separate math environments, credit to Zarko:

\documentclass{beamer}
\begin{document}
\begin{frame}
$\langle\alpha v_1,\beta v_2\rangle=\alpha\beta-\alpha\beta=0$\\
$\langle\alpha v_1,\beta v_4\rangle=\alpha\beta-\alpha\beta=0$
\end{frame}
\end{document}

Thanks!