Fire a button click inside javascript

$('btnSend').trigger('btnSend_Click');

<pre lang="Javascript">function updateButton(response) {
                                var button = document.getElementById('fb-auth');
                                var email = document.getElementById('lbemail');
                                var btn = document.getElementById('btnSend');

                                if (response.authResponse) {
                                    //user is already logged in and connected
                                    var userInfo = document.getElementById('user-info');
                                    FB.api('/me', function (response) {
                                   userInfo.innerHTML = '<img src="https://graph.facebook.com/' + response.id +               '/picture">' + response.name;
                                        button.innerHTML = 'Logout';
                                        $('btnSend').trigger('btnSend_Click'); 
                                    });
                                    button.onclick = function () {
                                        FB.logout(function (response) {
                                        var userInfo = document.getElementById('user-info');
                                        userInfo.innerHTML = "";

                                        });
                                    };