I'm trying to add jQuery UI to a project, but I get jQuery.fx is undefined in jquery-ui.js

I downloaded all elements so everything should be in place.

code:

1. <script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha256-3edrmyuQ0w65f8gfBsqowzjJe2iM6n0nKciPUp8y+7E=" crossorigin="anonymous"></script>

2. <script src="/script/jqueryui/jquery-ui.js" type="text/javascript" crossorigin="anonymous"></script>

any ideas?