JSFiddle - React, Tailwind, and code Playground
HTML
<div id="test1">Test 1</div>
<div id="test1_sub"> Test 1 Sub</div>
JavaScript
$( "div[id^='test1']" ).fadeOut();
<div id="test1">Test 1</div>
<div id="test1_sub"> Test 1 Sub</div>
$( "div[id^='test1']" ).fadeOut();