ASINH(3M)ASINH(3M)


NAME
     acosh, asinh, atanh, acoshf, asinhf, atanhf, cacosh, cacoshl, cacoshf,
     casinh, casinhf, casinhl, catanh, catanhf, catanhl - inverse
     hyperbolic functions

SYNOPSIS
     #include <math.h>

     double acosh(double x);
     float acoshf(float x);

     double asinh(double x);
     float asinhf(float x);

     double atanh(double x);
     float atanhf(float x);

     #include <complex.h>

     double complex cacosh(double complex z);
     float complex cacoshf(float complex z);
     long double complex cacoshl(long double complex z);

     double complex casinh(double complex z);
     float complex casinhf(float complex z);
     long double complex casinhl(long double complex z);

     double complex catanh(double complex z);
     float complex catanhf(float complex z);
     long double complex catanhl(long double complex z);

DESCRIPTION
     The catanh, cacosh, and casinh functions are not available for
     programs compiled with the O32 ABI.

     The acosh functions compute the non-negative inverse hyperbolic cosine
     of x.  The asinh functions compute the inverse hyperbolic sine of x.
     The atanh functions compute the inverse hyperbolic tangent of x.

     The cacosh functions compute the complex inverse hyperbolic cosine of
     z, with a branch cut at values less than 1 along the real axis.  The
     casinh functions compute the complex inverse hyperbolic sine of z,
     with branch cuts outside the interval [-i,+i] along the imaginary
     axis.  The catanh functions compute the complex inverse hyperbolic
     tangent of z, with branch cuts outside the interval [-1, +1] along the
     real axis.

     Roundoff errors are derived from log1p, described in exp(3M).

     Functions in the standard math library (libm.a) are referred to as -lm
     versions. Those in libmx library (libmx.a) are referred to as -lmx
     versions, and those in the the BSD math library (libm43.a) are
     referred to as -lm43 versions.  The complex functions are only
     available in libm and libmx.

NOTES
     Long double operations on this system are only supported in round to
     nearest rounding mode (the default).  The system must be in round to
     nearest rounding mode when calling any of the long double functions,
     or incorrect answers will result.

RETURN VALUES
     The -lm and -lmx versions always return the default Quiet NaN and set
     errno to EDOM when a NaN is used as an argument.  A NaN argument
     usually causes the -lm43 versions to return the same argument.  The
     -lm43 versions never set errno.

     acosh returns the default quiet NaN if the argument is less than 1.
     The -lm and -lmx versions also set errno to EDOM.

     atanh returns the default quiet NaN if the argument has an absolute
     value greater than 1.  The -lm and -lmx versions also set errno to
     EDOM.

     See matherr(3M) for a description of error handling for -lmx
     functions.

SEE ALSO
     math(3M), exp(3M), matherr(3M)