Use Math.PI to do calculation in JavaScript

Description

The following code shows how to use Math.PI to do calculation.

Example


<!DOCTYPE html>
<html>
<head>
<script type="text/javascript">
var number = new Number(123);<!--  w w  w . ja  v a  2 s .c o  m-->
document.write("<P>You entered a radius of " + number + "</p>");
document.write("<P>The area of the circle is " + (number * number * Math.PI) + "</p>");
document.write("<P>The circumference of the circle is " + (2 * number * Math.PI) + "</p>");
</script>
</head>
<body>
</body>
</html>

Click to view the demo

The code above generates the following result.

$Use Math.PI to do calculation in JavaScript$

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