Returns the cosine of a given angle.
This function works the same in Google Sheets as it does in Excel — same syntax and arguments.
COS(number)The COS function calculates the cosine of an angle provided in radians. If your angle is in degrees, you must multiply it by PI()/180 or use the RADIANS function to convert it.
=COS(0)Result: 1
Returns the cosine of 0 radians, which is 1.
=COS(RADIANS(60))Result: 0.5
Converts 60 degrees to radians and returns the cosine, which is 0.5.
Excel expects the input to be in radians. If your input is in degrees, ensure you convert it using the RADIANS function.