JSFiddle - React, Tailwind, and code Playground

HTML

<link rel="stylesheet" href="http://getbootstrap.com/dist/css/bootstrap.min.css">

<div class="input-group">
      <span class="input-group-addon" id="dollar" style="display:none;">$</span>
    <input  id="test" type="text" class="form-control" aria-label="Amount (to the nearest dollar)" />
</div>

JavaScript

$('#test').keypress(function() {
          $('#dollar').fadeIn(1000);
     });