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Manual Reference Pages  - CACOS (3)

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cacos, cacosf, cacosl - complex arc cosine

CONTENTS

Synopsis
Description

#include <complex.h>

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 acos(). If y = cacos(z), then z = ccos(y). The real part of y is chosen in the interval [0,pi].

One has cacos(z) = -i clog(z+csqrt(z*z-1)).

C99

ccos(3), clog(3), complex(7)