I'm trying to export a PDF of a LyX document (it has never caused a problem before). Below I have posted pictures of the error message along with the equation LyX highlighted for me. I don't know what \hbox is, and I didn't use that in my code. Can someone please help me edit the equation so that I can export a PDF?


\hboxthing is just an example for a typo, has nothing to do with your text! – vaettchen Feb 1 at 16:57