What is the error in following code related to font icon?

<div class="col-xs-4">
      <i class="fa fa-thumbs-up"><button class="btn btn-block btn-primary">Like</button></i>


In the above mentioned code of line, I am not able to see the font awesome icon before button. So, I want help to solve this error.

Thanks in advance!!!

The <i> should be nested in the <button>, not the other way around.