Math.acos()

Syntax

Math.acos(x)

Parameters

x

숫자 형식.

Return value

[-1, 1]의 숫자를 입력했을 때, 입력한 숫자의 코사인 역함수 값을 반환한다. 그 외의 숫자를 입력하면, NaN을 반환한다.

Description

The Math.acos() method returns a numeric value between 0 and π radians for x between -1 and 1. If the value of x is outside this range, it returns NaN.

Because acos() is a static method of Math, you always use it as Math.acos(), rather than as a method of a Math object you created (Math is not a constructor).

Examples

Using Math.acos()

Math.acos(-2);  // NaN
Math.acos(-1);  // 3.141592653589793
Math.acos(0);   // 1.5707963267948966
Math.acos(0.5); // 1.0471975511965979
Math.acos(1);   // 0
Math.acos(2);   // NaN

For values less than -1 or greater than 1, Math.acos() returns NaN.

Specifications

Browser compatibility

See also

• Math.asin()
• Math.atan()
• Math.atan2()
• Math.cos()
• Math.sin()
• Math.tan()