asinh, asinhf, asinhl

Header: <math.h>

1-3) Computes the inverse hyperbolic sine of arg.

# Declarations

float asinhf( float arg );

(since C99)

double asinh( double arg );

(since C99)

long double asinhl( long double arg );

(since C99)

#define asinh( arg )

(since C99)

# Parameters

# Return value

If no errors occur, the inverse hyperbolic sine of arg (sinh-1(arg), or arsinh(arg)), is returned.

# Notes

Although the C standard names this function “arc hyperbolic sine”, the inverse functions of the hyperbolic functions are the area functions. Their argument is the area of a hyperbolic sector, not an arc. The correct name is “inverse hyperbolic sine” (used by POSIX) or “area hyperbolic sine”.

# Example

#include <math.h>
#include <stdio.h>
 
int main(void)
{
    printf("asinh(1) = %f\nasinh(-1) = %f\n", asinh(1), asinh(-1));
    // special values
    printf("asinh(+0) = %f\nasinh(-0) = %f\n", asinh(0.0), asinh(-0.0));
}

# See also