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csqrt, csqrtf, csqrtl – complex square root
USAGE
#include <complex.h>

double complex csqrt(double complex z);
float complex csqrtf(float complex z);
long double complex csqrtl(long double complex z);

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cexp, cexpf, cexpl – complex exponential function
USAGE
#include <complex.h>

double complex cexp(double complex z);
float complex cexpf(float complex z);
long double complex cexpl(long double complex z);

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cexp2, cexp2f, cexp2l – base-2 exponent of a complex number
USAGE
#include <complex.h>

double complex cexp2(double complex z);
float complex cexp2f(float complex z);
long double complex cexp2l(long double complex z);

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complex – basics of complex mathematics
USAGE
#include <complex.h>

DESCRIPTION
Complex numbers are numbers of the form z = a+b*i, where a and b are
real numbers and i = sqrt(-1), so that i*i = -1.
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