JavaScript - Math acos Method

Description

This method returns the arccosine in radians of a number. The acos method returns a numeric value between 0 and pi radians for x between -1 and 1. If the value of number is outside this range, it returns NaN.

Syntax

Its syntax is as follows −

Math.acos( x ) ;

Parameter Details

x − A number.

Return Value

Returns the arccosine in radians of a number.

Example

Try the following example program.

Live Demo

<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>

Output

First Test Value : 3.141592653589793
Second Test Value : 1.5707963267948966
Third Test Value : NaN
Fourth Test Value : NaN

javascript_math_object.htm