Excel - Microsoft Excel ACOS Function

Description

The Excel ACOS function calculates the arccosine (ie. the inverse cosine) of a given number, and returns an angle, in radians, between 0 and p. 

The format of the function is : 

ACOS( number ) 

Where the number argument is the value, between -1 and +1, for which you want to calculate the arccosine. 

Converting from Radians to Degrees 

If you want the angle returned by the Acos function to be expressed in degrees, you can convert it, using the Excel Degrees function: 

=DEGREES( radians ) 

An example of this is given below. 

Excel Acos Function Examples

Column A of the spreadsheet below, shows examples of the Excel Acos Function, used to calculate the arccosine of different values. In the example in cell A4, the result is converted from radians, into degrees.