xóa hết dữ liệu trong ô text box dùng jquery

<script src="//ajax.googleapis.com/ajax/libs/jquery/1.7.1/jquery.min.js" type="text/javascript"></script>
 <script type="text/javascript">
        $(document).ready(function () {
            $("#btn").click(function () {
                $("input[type=text]").val("");
                $("textarea").val("");
            });
        });
 </script>
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<input type="text" />
<input type="text" />
<textarea cols="2" rows="2"></textarea>
<textarea cols="2" rows="2"></textarea>
<input type="button" value="go" id="btn" />