CODE EXAMPLE FOR JAVASCRIPT

radio button enable and requerd in jquery

<div id="myDiv">
  <input type="radio" name="sex" value="male" disabled="disabled" /> Male<br />
</div>
<input type="radio" name="sex" value="female" /> Female
<br />

<input id="myButton" type="button" value="click here" />

  $("#myButton").click(function(){
    $("#myDiv").find("input").removeAttr("disabled");
})