Index for Section 3

Alphabetical listing for A

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asinh(3)
NAME
  asinh, acosh, atanh - Compute inverse hyperbolic functions

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 );

LIBRARY
  Math Library (libm)

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

  asinh():  XPG4-UNIX

  acosh():  XPG4-UNIX

  atanh():  XPG4-UNIX

  Refer to the standards(5) reference page for more information about
  industry standards and associated tags.

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
  ___________________________________________________

Index for Section 3

Alphabetical listing for A

Top of page