How to hide element using Twitter Bootstrap and show it using jQuery?

Let’s say I create an HTML element like this,

<div id="my-div" class="hidden">Hello, TB3</div>
<div id="my-div" class="hide">Hello, TB4</div>
<div id="my-div" class="d-none">Hello, TB4</div>

How could I show and hide that HTML element from jQuery/Javascript.

JavaScript:

$(function(){
  $("#my-div").show();
});

Result: (with any of these).

I would like the elements above to be hidden.

What is simplest way to hide element using Bootstrap and show it using jQuery?