I am trying to figure out how to write a set. This should be simple! I've got
S = {1,2,3,4}
and it won't work?
PS Oops. I guess it did. Sorry.
[tex]S=\{1,2,3,4\}[/tex] gives $\displaystyle S=\{1,2,3,4\} $
Click on the “go advanced” tab. On the toolbar you will see $\displaystyle \boxed{\Sigma}$ clicking on that give the LaTeX wraps, [tex] [/tex]. The code goes between them.