We do not offer this functionality out of the box. What you can do is set a particular page to include RadScriptManager from its Title and Properties menu, or alternatively place the [RequireScriptManager] attribute on your class and this should automatically add RadScriptManager on the page where your control is dropped. Concerning RadAjaxManager, you can place it on your masterpage (actually you'd better place RadAjaxManagerProxy and then place RadAjaxManager on your control.
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