acos[]

Returns the arc cosine of number, expressed in degrees.

The acos[] function is a function that returns the arc cosine of a number. The arc cosine, or inverse cosine, of a number is the angle (in degrees) whose cosine is equal to the given number. The input to the function should be a value between -1 and +1, and the output will be in the range of 0 to 180 (degrees). For example, acos[1] would return 0 and acos[0.5] would return 60.

Syntax

acos[x]

Parameters

x Number whose arc cosine is computed, in the interval [-1,+1].
Return Value Principal arc cosine of x, in the interval [0,180] degrees.
If the argument is out of interval, return value is NaN.

Examples

#<result> = acos[0]
(print,#<result>)

result: 90 

#<result> = acos[1]
(print,#<result>)

result: 0 

#<result> = acos[0.5]
(print,#<result>)

result: 60

See also

sin, asin, cos, tan, atan, atan2, pi