I've inherited a fairly substantial LaTeX document as part of a new job. Unfortunately, I haven't really had time to get to grips with it and it now need to be compiled.
There are no errors (other than some biblatex warnings) but none of the mathematical operators are showing up (=, +, -, > etc.) except for \times. I've done some research and have come to the conclusion it's probably a conflict in the packages being used but I can't seem to figure out which one.
The preamble is:
\RequirePackage{xcolor} % Extended colorsx
\documentclass{BYUTextbookUCTAS}
\usepackage{natbib}
\usepackage[immediate,save]{silence}
\usepackage[T1]{fontenc}
\usepackage{lmodern} %definitely need this
\usepackage{amsmath,amssymb}
\usepackage{rotating}
\usepackage{threeparttable}
\usepackage{tikz}
\usepackage[tikz]{bclogo}
\usepackage{bigstrut}
\usepackage{booktabs}
\usepackage{lifecon}
\usepackage{multirow}
\usepackage{longtable}
\usepackage{arydshln}
% Sub appendices
\usepackage{appendix}
\usepackage{chngcntr}
\usepackage{etoolbox}
Edit: Thanks to egreg, I've managed to get the mathematical operators back but now there are some other formatting problems.
I've uploaded a PDF here showing what happens when I include/exclude the "lmodern" package.
\usepackage{lmodern}is the culprit. – egreg Feb 20 '20 at 09:21BYUTextbookUCTAS? And I also thought it might be\usepackage{lmodern}but everything fell apart when I removed that. – Flobagob Feb 20 '20 at 09:25BYUTextbookUCTAS, but it's not generally available and a Google search didn't help. – egreg Feb 20 '20 at 09:42\usepackage{lmodern}- when I remove it, the operators return. Except then all the alignment is out etc. Is this to do with the document class? – Flobagob Feb 20 '20 at 09:44\usepackage{fourier}so all math characters get redefined to the non standard encoding sused by those fonts so if you switch back to latin modern then the math is broken. – David Carlisle Feb 20 '20 at 16:44lifeconpackage is not available and nobody but you can tell how to show the blue bars. Please, open a new question with the details. – egreg Feb 20 '20 at 16:49