Returns the inverse hyperbolic cosine of a number. Number must be greater than or equal to 1. The inverse hyperbolic cosine is the value whose hyperbolic cosine is number, so ACOSH(COSH(number)) equals number.
Syntax
ACOSH(number)
Number is any real number equal to or greater than 1.
Example
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Selecting an example from Help
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A 
B 
Formula 
Description (Result) 
=ACOSH(1) 
Inverse hyperbolic cosine of 1 (0) 
=ACOSH(10) 
Inverse hyperbolic cosine of 10 (2.993223) 
