CACOSH(3)						   BSD Library Functions Manual 						 CACOSH(3)

NAME

     cacosh -- complex inverse hyperbolic cosine function

SYNOPSIS

     double complex
     cacosh(double complex z);

     long double complex
     cacoshl(long double complex z);

     float complex
     cacoshf(float complex z);

DESCRIPTION

     cacosh(z) computes the inverse hyperbolic cosine of the complex floating-point number z, with a branch cut on the interval [-inf, 1] along
     the real axis.

     cacosh() returns values in a half-strip of the complex plane with positive real part and imaginary part in the interval [-Pi, Pi].

     For all complex floating point numbers z, cacosh(conj(z)) = conj(cacosh(z)).

SPECIAL VALUES

     The conjugate symmetry of cacosh() is used to abbreviate the specification of special values.

     cacosh(+-0 + 0i) returns 0 + Pi/2 i.

     cacosh(x + inf i) returns inf + Pi/2 i, for finite x.

     cacosh(x + NaN i) returns NaN + NaN i, for finite nonzero x.

     cacosh(-inf + yi) returns inf + Pi i, for finite positive-signed y.

     cacosh(inf + yi) returns inf + 0i, for finite positive-signed y.

     cacosh(-inf + inf i) returns inf + 3Pi/4 i.

     cacosh(inf + inf i) returns inf + Pi/4 i.

     cacosh(+-inf + NaN i) returns inf + NaN i.

     cacosh(NaN + yi) returns NaN + NaN i, for finite y.

     cacosh(NaN + inf i) returns inf + NaN i.

     cacosh(NaN + NaN i) returns NaN + NaN i.

NOTES

SEE ALSO

     ccosh(3) complex(3)

STANDARDS

     The cacosh() function conforms to ISO/IEC 9899:2011.

4th Berkeley Distribution					 December 11, 2006					 4th Berkeley Distribution