CACOSH(3)		   Linux Programmers Manual		    CACOSH(3)



NAME
       cacosh, cacoshf, cacoshl - complex arc hyperbolic cosine

SYNOPSIS
       #include 

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

       Link with -lm.

DESCRIPTION
       The  cacosh()  function calculates the complex arc hyperpolic cosine of
       z.  If y = cacosh(z), then z = ccosh(y).  The imaginary part  of  y  is
       chosen in the interval [-pi,pi].  The real part of y is chosen non-neg
       ative.

       One has:

	   cacosh(z) = (0.5) * clog((1 + z) / (1 - z))

CONFORMING TO
       C99.

SEE ALSO
       acosh(3), cabs(3), cimag(3), complex(7)

COLOPHON
       This page is part of release 3.05 of the Linux  man-pages  project.   A
       description  of	the project, and information about reporting bugs, can
       be found at http://www.kernel.org/doc/man-pages/.



				  2007-12-26			     CACOSH(3)