Add scripts common to master page and content page

Question

Hello,
        I added the scripts in head tag of master page. Those are 

<link href="Styles/autocomplete-jquery.autocomplete.css" rel="stylesheet" />

            <link href="Styles/MasterStyles.css" rel="stylesheet" />

            <script src="Scripts/autocomplete-jquery-1.6.2.min.js" type="text/javascript"></script>

            <script src="Scripts/autocomplete-jquery.autocomplete.js" type="text/javascript"></script>

But in content page these are not working, but if i added these scripts in content page then its working  which is meaning less adding in content page and master page.
Plz answer me