im using jqurey to develop in web enviorment. i want to know why

 $("#a#trigger").trigger('mouseenter');
 $("#a#trigger").trigger('hover');
 $("#a#trigger").trigger('mouseover');

all 3 of those aren't working to active a hover function i have.

$(function() {


        $('a#trigger').hover(function(e) {
          $('div#pop-up').show();

             }, function() {
          $('div#pop-up').hide();
        });

     });

      });

a#trigger is the name of the anchor, and #pop-up is a div element in my web.

problem is, that i want to mouse over some event in FullCalendar plugin and those functions aint working. Thanks.