Calculates the inverse hyperbolic sine of a number

include <math.h>
double asinh ( double x  );
float asinhf ( float x  );
long double asinhl ( long double x  );

The asinh( ) functions return the number whose hyperbolic sine is equal to the argument x.

Example

puts("   x          asinh(x)        log( x + sqrt(x*x+1))\n"
     "-------------------------------------------------------");
for ( double x = -2.0; x < 2.1; x += 0.5)
  printf("%6.2f %15f %20f\n", x, asinh(x), log( x + sqrt(x*x+1)));

This code produces the following output:

   x          asinh(x)        log( x + sqrt(x*x+1))
-------------------------------------------------------
 -2.00       -1.443635            -1.443635
 -1.50       -1.194763            -1.194763
 -1.00       -0.881374            -0.881374
 -0.50       -0.481212            -0.481212
  0.00        0.000000             0.000000
  0.50        0.481212             0.481212
  1.00        0.881374             0.881374
  1.50        1.194763             1.194763
  2.00        1.443635             1.443635

See Also

Other hyperbolic trigonometry functions for real numbers: acosh( ), atanh( ), sinh( ), cosh( ), and tanh( ); the hyperbolic sine and inverse hyperbolic sine functions for complex numbers: csinh( ) and casinh( )