COS function
Returns the cosine of the given angle.
Syntax
COS(number)
Number is the angle in radians for which you want the cosine.
Remark
If the angle is in degrees, either multiply the angle by PI()/180 or use the RADIANS function to convert the angle to radians.
Example
The example may be easier to understand if you copy it to a blank worksheet.
How to copy an example

Create a blank workbook or worksheet.

Select the example in the Help topic.
Note Do not select the row or column headers.
Selecting an example from Help

Press CTRL+C.

In the worksheet, select cell A1, and press CTRL+V.

To switch between viewing the results and viewing the formulas that return the results, press CTRL+` (grave accent), or on the Formulas tab, in the Formula Auditing group, click the Show Formulas button.

