Purpose
Return value
Syntax
=ATANH(number)
- number - The number to get the inverse hyperbolic tangent of.
Using the ATANH function
The Excel ATANH function returns the inverse hyperbolic tangent of a number. Given 0.5 as input, the function returns 0.549306144 as output.
=ATANH(0.5) // returns 0.549306144
Explanation
The hyperbolic arc tangent function is the inverse of the TANH function.
=ATANH(TANH(x)) // returns x
The plot below shows the output of the ATANH function in Excel.
Notes:
- Given output greater than or equal to 1.0 or less than or equal to -1.0, throws a #NUM error.
Purpose
Return value
Syntax
=COS(number)
- number - The angle in radians for which you want the cosine.
Using the COS function
The COS function returns the cosine of an angle provided in radians. In geometric terms, the cosine of an angle returns the ratio of a right triangle’s adjacent side over its hypotenuse. For example, the cosine of PI()/6 radians (30°) returns the ratio 0.866.
=COS(PI()/6) // Returns 0.886
Using Degrees
To supply an angle to COS in degrees, multiply the angle by PI()/180 or use the RADIANS function to convert to radians. For example, to get the COS of 60 degrees, you can use either formula below:
=COS(60*PI()/180)
=COS(RADIANS(60))
Explanation
The graph of cosine above visualizes the output of the function for all angles from 0 to a full rotation. Geometrically, the function returns the x -component of the point corresponding to an angle on the unit circle. Since the cosine of an angle returns a ratio, the output of the function will always be in the range [-1, 1].
Graph courtesy of wumbo.net
