This method returns the arc cosine of radians. The ACOS method returns the value of 0 and PI for radians between x-1 and 1. If the number value is outside this range, NaN is returned.
Grammar
Math.acos( x ) ;
Here are the details of the parameters:
Return value:
Example:
<html>
<head>
<title>JavaScript Math acos() Method</title>
</head>
<body>
<script type="text/javascript">
var value = Math.acos(-1);
document.write("First Test Value : " + value );
var value = Math.acos(null);
document.write("<br />Second Test Value : " + value );
var value = Math.acos(30);
document.write("<br />Third Test Value : " + value );
var value = Math.acos("string");
document.write("<br />Fourth Test Value : " + value );
</script>
</body>
</html>
This will produce the following results:
First Test Value : 3.141592653589793 Second Test Value : 1.5707963267948965 Third Test Value : NaN Fourth Test Value : NaN
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