Re: hyperbolic functions - set angle degrees

[Ethan A M. <sf...@us...>]

On Monday, July 16, 2012 12:39:28 pm Bastian Märkisch wrote:
> While looking into the complex hyperbolic functions, I noticed that asinh, acosh and atanh honour 'set angle degree' setting, while sinh, cosh and tanh do not. I know this is documented (see 'help set angles'). But I am curious if anybody remembers the rationale behind this. Is it because of relations like asinh(x) = -i asin(i x)?
>  I have also tried out various pocket calculators and a few calculator programs, but none of them considered the deg/rad setting for the (inverse) hyperbolic functions.
> 

I think that is because their domain is not "angles" but instead "hyperbolic angles".
See
	http://en.wikipedia.org/wiki/Hyperbolic_angle

Under this interpretation the independent variable is not in radians to begin with,
so converting it to degrees does not make sense.

	Ethan