forms – Hide field dynamically with a click on any radio list option

I have two radio list fields in a form. I need to hide field1 when any option in field2 is clicked. There are loads of examples for doing this when toggling on a specific radio option, but I can’t seem to get the syntax right to trigger the hide when clicking on ANY option in the main radio list. This is what I have so far:

$(function() {
  $("input(name='optionName(und)')").click(function() {
    if ($("#chkYes").is(":checked")) {
    } else {

This isn’t working, and I’ve tried several syntax variations, but most of the solutions I found are for plain JavaScript, not jQuery.