acosh

fnreal acosh(real x) @safe pure nothrow @nogc

Calculates the inverse hyperbolic cosine of x.

Mathematically, acosh(x) = log(x + sqrt( x*x - 1))

1..∞,

0..∞

x, acosh(x) NaN, NaN <1, NaN 1, 0 +∞,+∞
fndouble acosh(double x) @safe pure nothrow @nogc

ditto

fnfloat acosh(float x) @safe pure nothrow @nogc

ditto