Returns the hyperbolic arc sine of its argument.

    This function is supported on OpenVMS Integrity servers and
    Alpha only.

    Format

      #include  <math.h>

      double asinh  (double x);

      float asinhf  (float x);

      long double asinhl  (long double x);

1  –  Argument

 x

    A radian expressed as a real value in the domain [-Infinity,
    +Infinity].

2  –  Description

    The asinh functions return the hyperbolic arc sine of x for x
    in the domain [-Infinity, +Infinity], where asinh(x) = ln(x +
    sqrt(x**2 + 1)).

    The asinh function is the inverse function of sinh where
    asinh(sinh(x)) = x.