NAME

acosh, asinh, atanh - inverse hyperbolic functions

 SYNOPSIS

#include <math.h>

double acosh(double x);
double asinh(double x);
double atanh(double x);

 DESCRIPTION

The acosh(), asinh() and atanh() functions compute the inverse hyperbolic cosine, sine, and tangent of their argument, respectively.

 RETURN VALUE

The acosh(), asinh() and atanh() functions return the inverse hyperbolic cosine, sine, and tangent of their argument, respectively.

The acosh() function returns an implementation-dependent value (NaN or equivalent if available) and sets errno to [EDOM] when its argument is less than 1.0.

The atanh() function returns an implementation-dependent value (NaN or equivalent if available) and sets errno to [EDOM] when its argument has absolute value greater than 1.0.

If x is NaN, the asinh(), acosh() and atanh() functions return NaN and may set errno to [EDOM].

 ERRORS

The acosh() function will fail if:

[EDOM]

The x argument is less than 1.0.

The atanh() function will fail if:

[EDOM]

The x argument has an absolute value greater than 1.0.

The atanh() function will fail if:

[ERANGE]

The x argument has an absolute value equal to 1.0

The asinh(), acosh() and atanh() functions may fail if:

[EDOM]

The value of x is NaN.

 EXAMPLES

None.

 APPLICATION USAGE

None.

 FUTURE DIRECTIONS

None.

 SEE ALSO

cosh(), sinh(), tanh(), <math.h>.