A very common gotcha here might be the following:
Leading or trailing spaces are not allowed in the pandoc extension tex_math_dollars, which is used by nbconvert.
This means, that this won't work:
$ \epsilon \gt 0 $
And we see the error message:
! Missing $ inserted.
<inserted text>
$
l.364 \$ \epsilon
\gt 0 \$
?
! Emergency stop.
<inserted text>
$
l.364 \$ \epsilon
\gt 0 \$
No pages of output.
Transcript written on notebook.log.
The correct formula without spaces works fine:
$\epsilon \gt 0$
This seems to be a bug in Jupyter nbconvert.
The pandoc documentation suggests that for pandoc this is by design to allow to use dollar symbols without escape sequence:
Anything between two $ characters will be treated as TeX math. The
opening $ must have a non-space character immediately to its right,
while the closing $ must have a non-space character immediately to its
left, and must not be followed immediately by a digit. Thus, $20,000
and $30,000 won’t parse as math. If for some reason you need to
enclose text in literal $ characters, backslash-escape them and they
won’t be treated as math delimiters.