acosh() returns the hyperbolic arc cosine of x for x in the
interval [1,+infinity]. acosh(x) = ln(x + sqrt(x**2 - 1)).
acosh() is the inverse function of cosh(). The definition of the
acosh() function is acosh(cosh (x)) = x.
Entry-Point Names
Generic
Function Data Type OpenVMS Tru64 UNIX
Name Required
acosh S_FLOAT math$acosh_s acoshf
T_FLOAT math$acosh_t acosh
X_FLOAT math$acosh_x acoshl
F_FLOAT math$acosh_f
G_FLOAT math$acosh_g