The shell command<br />"/l/www/moodle/filter/tex/mimetex.linux" -e "/m/floppy/avle/moodledata/filter/tex/49690efd08f29ae55130e7ef1689ad1b.gif" -- '\Large 
  \nabla f(a,b)\cdot \mathbf{r}'\''(0)=0,
  '<br />returned status = 126<br />
Image not found!<br />Please try the <a href="https://mycourses.aalto.fi/filter/tex/texdebug.php">debugging script</a>