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CASIN(3)                 BSD Library Functions Manual                 CASIN(3)

NAME
     casin -- complex inverse sine function
     catan -- complex inverse tangent function

SYNOPSIS
     #include <complex.h>

     double complex
     casin(double complex z);

     long double complex
     casinl(long double complex z);

     float complex
     casinf(float complex z);

     double complex
     catan(double complex z);

     long double complex
     catanl(long double complex z);

     float complex
     catanf(float complex z);

DESCRIPTION
     casin(z) computes the inverse sine of the complex floating-point number
     z, with branch cuts outside the interval [-1, 1] on the real axis.

     ctan(z) computes the inverse tangent of the complex floating-point number
     z, with branch cuts outside the interval [-i, i] on the imaginary axis.

     Both functions return values in a strip of the complex plane with
     unbounded imaginary part, and real part in the interval [-Pi/2, Pi/2].

NOTES
     casin and catan are defined in terms of the complex inverse hyperbolic
     functions as follows:

           casin(z) = -i * casinh(i*z),
           catan(z) = -i * catanh(i*z).

SEE ALSO
     casinh(3) catanh(3) complex(3)

STANDARDS
     The casin() and catan() functions conform to ISO/IEC 9899:2011.

4th Berkeley Distribution      December 11, 2006     4th Berkeley Distribution