Manual of CCOS(3) (v2.65)

Linux Programmer's Manual

NAME

ccos, ccosf, ccosl - complex cosine function

#include <complex.h>

double complex ccos(double complex z);
float complex ccosf(float complex z);
long double complex ccosl(long double complex z);

Link with -lm.

The complex cosine function ccos(z) is defined as (exp(i*z)+exp(-i*z))/2.

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