CASINH(3) | Library Functions Manual | CASINH(3)

# NAME

`casinh`, `casinhf`, `casinhl` — complex inverse hyperbolic sine

# SYNOPSIS

Math Library (libm, -lm)
`#include <complex.h>`

double complex
`casinh`(double complex z);

float complex
`casinhf`(float complex z);

long double complex
`casinhl`(long double complex z);

# DESCRIPTION

The `casinh`(), `casinhf`() and `casinhl`() functions compute the complex inverse hyperbolic sine of z.

For all complex floating-point numbers z,

    casinh(z) = -i casin(iz).

# RETURN VALUES

The `casinh`(), `casinhf`() and `casinhl`() functions return the complex inverse hyperbolic sine of z with imaginary part in the interval [-Pi/2, Pi/2], and unbounded real part.

# SEE ALSO

cacosh(3), catanh(3)

# STANDARDS

The `casinh`(), `casinhf`() and `casinhl`() functions conform to ISO/IEC 9899:1999 (“ISO C99”).

June 7, 2025 | Debian