acosh Inverse hyperbolic cosine &reftitle.description; floatacosh floatarg Returns the inverse hyperbolic cosine of arg, i.e. the value whose hyperbolic cosine is arg. &reftitle.parameters; arg The value to process &reftitle.returnvalues; The inverse hyperbolic cosine of arg &reftitle.changelog; &Version; &Description; 5.3.0 This function is now available on all platforms &reftitle.seealso; cosh acos asinh atanh