problem with js

problem with js

hello i have this on my js code 
$(document).on('pagecreate', '#VHC', function(){  
        //$(document).on('click', '#button_vhc', function() 
{
$.ajax({
        type: "POST",
            //url: "vehicules.php",
            success: function(result) 
{
document.getElementById("cout").value= "<li id=\"cout\">salim</li>";
//alert(obj.value);
}
});
}
// );
});


and this on my php
echo "<li>601802 PARTNER 6539TU149 TN, TUNIS, N8 2014/02/03 16:16:03   0 Km/h</li> ";



but in my html no thing displayed 
plz help