In my quizzes I tried to wrtie mathematical TEX Formulas. So I wrote e.g.:

dollar dollar sqrt(x)+x^2 dollar dollar ($$ sqrt(x)+x^2 $$)

But the formula does appear as a missing link (see attachment). I read in the documentation, one has to allow the browser to run binaries. But how? Or did a make another mistake?

Moodle 1.8, Debian Linux 4.0, Apache 2.x