%mathpiper,def="ArcCosh"

10 # ArcCosh(_x)_(InNumericMode() And (IsNumber(x) Or Type(x) = "Complex")) <-- N(Eval( Ln(x+Sqrt(x^2-1)) ));

200 # ArcCosh(Infinity) <-- Infinity;
200 # ArcCosh(-Infinity) <-- Infinity+I*Pi/2;
200 # ArcCosh(Undefined) <-- Undefined;

ArcCosh(xlist_IsList) <-- MapSingle("ArcCosh",xlist);

%/mathpiper