Angular: Empty Fiddle

http://angularjs.org/

HTML

<script src="http://code.angularjs.org/angular-1.0.1.js"></script>
<script src="https://c328740.ssl.cf1.rackcdn.com/mathjax/latest/MathJax.js?config=AM_HTMLorMML-full"></script>
<div ng-controller="MyCtrl">
    <input ng-model="math">
    <p data-math-exp data-value="math"></p>
</div>

JavaScript

var myApp = angular.module('myApp',[]);

//myApp.directive('myDirective', function() {});
//myApp.factory('myService', function() {});

function MyCtrl($scope) {
    $scope.name = 'Superhero';
}

myApp.directive("mathExp", function () {
    return {
        scope: {
            value: "="
        },
        link: function (scope, el) {

            var domEl = el[0];
            scope.$watch("value", function (newValue) {

                //nothing to do here
                if (newValue == null || window.MathJax == null)return;

                //update the dom with the new value and pass the hub for styling the equation
                domEl.innerHTML = '`' + newValue + '`';
                MathJax.Hub.Queue(["Typeset", MathJax.Hub, domEl]);
            });
        }
    }
});