$(document).ready(function() {
    $("#tex_update").click(function(){
        base_url = "http://chart.apis.google.com/chart?cht=tx&chf=bg,s,00000000&chl="
        formula = $.URLEncode($("#tex_input").val().replace(/[\n\s\t]+/g, ' ').replace(/\s$/, ''));
        $("#tex_url").html(base_url + formula);
        $("#tex_image").attr("src", base_url + formula);
    });
});