title: If radio button .is(':checked') - not working properly
body: <p>I have a javascript code to show a field when a radio button is check. The code works perfectly, but when I uncheck the radio, the field doesn't hide. It also shows a <code>&lt;span&gt;</code> when the radio button is checked, but when it's unchecked, also the span doesn't hide..</p>
  
  <pre><code>&lt;script&gt;
  $(function() {
      $('#radiopromo2').live('change', function() {
          if($(this).is(':checked')) {
              $("#fieldtraining").show();
              $("#radio3").show();
          } else {
              $("#fieldtraining").hide();
              $("#radio3").hide();
          }
      }).trigger('change');
  });
  &lt;/script&gt;
  </code></pre>
  
  <p>Anyone who can help me? I made a jsfiddle <a href="http://jsfiddle.net/4UH2H/8/" rel="nofollow">http://jsfiddle.net/4UH2H/8/</a></p>