Edit in JSFiddle

$(document).ready(function() {
  var arrFirst = [50, 10, 19, 22];
  var arrSecond = [6, 74]; 
  $('#firstPart').html(arrFirst.join("<br />"));
  $('#secondPart').html(arrSecond.join("<br />"));
  var arrJoin = arrFirst.concat(arrSecond);
  $('#allElements').html(arrJoin.join("<br>"));
});

<h3> First array </h3>
<div id="firstPart"></div>
<br/>
<h3> Second array </h3>
<div id="secondPart"></div>
<br/>
<h3>After Joining two array elements </h3>
<div id="allElements"></div>
<br/>