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JavaScript cos() Method

Math Object Reference JavaScript Math Object

Definition and Usage

The cos() method returns the cosine of a number.

Syntax

Math.cos(x)

Parameter Description
x Required. A number

Tips and Notes

Note: The cos() method returns a numeric value between -1 and 1, which represents the cosine of the angle.

Example

Example

Return the cosine of different numbers:

<script type="text/javascript">

document.write(Math.cos(3) + "<br />");
document.write(Math.cos(-3) + "<br />");
document.write(Math.cos(0) + "<br />");
document.write(Math.cos(Math.PI) + "<br />");
document.write(Math.cos(2*Math.PI));

</script>

The output of the code above will be:

-0.9899924966004454
-0.9899924966004454
1
-1
1

Try it yourself »

Math Object Reference JavaScript Math Object

From http://www.w3schools.com (Copyright Refsnes Data)