Anche in questo modo non cambia nulla

codice:
<!DOCTYPE html>
<html>
	<head>
        <meta http-equiv="content-type" content="text/html; charset=utf-8">
        
        <script type="text/javascript" src="jquery-1.8.1.js"></script>

		<title>Titolo</title>
	
        <script type="text/javascript">
        $("#divTest1").text("Hello, world!");
        </script>
	</head>
	
	<body>
	    <div id="divTest1"></div>
	</body>
</html>