Acos()

The Acos() function returns the arccosine, also known as the inverse cosine, value of the argument (in radians).

Syntax

result := math.Acos(x)

Notes on the parameter:

• x is the value whose arccosine value is to be found.
• The range must be between -1 and 1.
• If the parameter is either less than -1 or greater than 1 it returns NaN.
• The value returned will be of type float64.

Example

The following code calculates the arccosine and prints out the result:

package main

import (
  "fmt"
  "math"
)

func main() {
  fmt.Println(math.Acos(-1))
  fmt.Println(math.Acos(1.23))
}

The output will be:

3.141592653589793
NaN