<html>
<body>
<h1>JavaScript Arrays</h1>
<h2>The flatMap() Method</h2>
<p id="demo"></p>
<script>
const myArr = [1, 2, 3, 4, 5, 6];
const newArr = myArr.flatMap(x => [x, x * 10]);
document.getElementById("demo").innerHTML = newArr;
</script>
</body>
</html>