CACOS(3) Linux Programmer's Manual CACOS(3)
cacos, cacosf, cacosl - complex arc cosine
double complex cacos(double complex z);
float complex cacosf(float complex z);
long double complex cacosl(long double complex z);
Link with -lm.
The cacos() function calculates the complex arc cosine of z. If
y = cacos(z), then z = ccos(y). The real part of y is chosen in the
cacos(z) = -i clog(z + csqrt(z * z - 1))
ccos(3), clog(3), complex(7)
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/.