how can i call javascript from masterpage ?

[Vino_Gays]

i trying to call datetimepicker.js file but am using master page so i got error plzzz help ......... thanks

<asp:Content ID="Content1" ContentPlaceHolderID="ContentPlaceHolder1" Runat="Server">

<script language="javascript" src="~/datetimepicker.js" type="text/javascript"></script>
<script language="JavaScript">
<!--
if (document.images)
{
calimg= new Image(16,16);
calimg.src="images/cal.gif";
}
//-->
</script>

<TD><INPUT name="txtDate" type="text" class="eStextM1" id="txtDate" size="25" runat="server">
<A href="javascript:NewCal('txtDate','ddmmyyyy')" runat="server" ><IMG height="16" alt="Pick a date" src="../images/cal.gif" width="16" border="0"></A>

</asp:Content >