Comparing two arrays and getting the non duplicate(not unique) values

gistfile1.js

<script type="text/javascript">
    var arr1=[1,2,3,4,5];
    var arr2=[3,4,5,7,8,9,6];
    $(document).ready(function(){
        var arr=$(arr1).not(arr2).get();
        alert(arr.length);
    });
</script>