Returns the inverse hyperbolic tangent of a number. Number must be between 1 and 1 (excluding 1 and 1). The inverse hyperbolic tangent is the value whose hyperbolic tangent is number, so ATANH(TANH(number)) equals number.
Syntax
ATANH(number)
Number is any real number between 1 and 1.
Example
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A 
B 
Formula 
Description (Result) 
=ATANH(0.76159416) 
Inverse hyperbolic tangent of 0.76159416 (1, approximately) 
=ATANH(0.1) 
Inverse hyperbolic tangent of 0.1 (0.10034) 
