## Linux and UNIX Man Pages

Test Your Knowledge in Computers #576
Difficulty: Medium
All programming languages have automatic garbage collection that monitors the dynamically allocated pieces of memory and determine if any variable in the program still references it. If the memory is no longer referenced, it is 'garbage' and becomes eligible to be 'collected'.
True or False?

# acosh(3m) [bsd man page]

```ASINH(3M)																 ASINH(3M)

NAME
asinh, acosh, atanh - inverse hyperbolic functions

SYNOPSIS
#include <math.h>

double asinh(x)
double x;

double acosh(x)
double x;

double atanh(x)
double x;

DESCRIPTION
These functions compute the designated inverse hyperbolic functions for real arguments.

ERROR (due to Roundoff etc.)
These  functions inherit much of their error from log1p described in exp(3M).  On a VAX, acosh is accurate to about 3 ulps, asinh and atanh
to about 2 ulps.  An ulp is one Unit in the Last Place carried.

DIAGNOSTICS
Acosh returns the reserved operand on a VAX if the argument is less than 1.

Atanh returns the reserved operand on a VAX if the argument has absolute value bigger than or equal to 1.

math(3M), exp(3M), infnan(3M)

AUTHOR
W. Kahan, Kwok-Choi Ng

4.3 Berkeley Distribution					   May 12, 1986 							 ASINH(3M)```

## Check Out this Related Man Page

```asinh(3)						     Library Functions Manual							  asinh(3)

NAME
asinh, acosh, atanh - Compute inverse hyperbolic functions

LIBRARY
Math Library (libm.a)

SYNOPSIS
#include <math.h>

double  asinh  (double x); float  asinhf (float	x); long double asinhl	   (long double x); double acosh  (double x); float  acoshf (float
x); long double acoshl	  (long double x); double atanh  (double x); float  atanhf (float  x); long double atanhl     (long double x);

STANDARDS
Interfaces documented on this reference page conform to industry standards as follows:

asinh():  XPG4-UNIX

acosh():  XPG4-UNIX

atanh():  XPG4-UNIX

DESCRIPTION
The asinh(), asinhf(), and asinhl() functions return the hyperbolic arc sine of x, in the range [-infinity,  +infinity]	where  asinh(x)  =
ln(x + sqrt(x**2 + 1)).	The asinh() function is the inverse function of sinh() where asinh(sinh(x)) = x.

The  acosh(),  acoshf(),  and acoshl() functions return the hyperbolic arc cosine of x, in the range [1, +infinity] where acosh(x) = ln(x +
sqrt(x**2 - 1)).  The acosh() function is the inverse function of cosh() where acosh(cosh(x)) = |x|.

The atanh(), atanhf()  and atanhl() functions return the hyperbolic arc tangent of x, in the range (-1, 1).  The atanh()  function  is  the
inverse function of tanh() where atanh(tanh(x)) = x.

The following table describes function behavior in response to exceptional arguments:

---------------------------------------------------
Function   Exceptional Argument	 Routine Behavior
---------------------------------------------------
asinh()	  None			 N/A
asinhf()   None			 N/A
asinhl()   None			 N/A
acosh()	  x<1			 Invalid argument
acoshf()   x<1			 Invalid argument
acoshl()   x<1			 Invalid argument
atanh()	  x>1 or x=1		 Invalid argument
atanhf()   x>1 or x=1		 Invalid argument
atanhl()   x>1 or x=1		 Invalid argument
---------------------------------------------------
delim off

asinh(3)```