[Cfp-interest 3055] casinh(x + iNaN) - Annex G.6.3.2

Damian McGuckin damianm at esi.com.au
Sat Mar 16 03:41:34 PDT 2024


The 4th item in the Dash List says

 	casinh(x + i NaN) = NaN + i NaN for finite x

Now, for x = 0

 	casinh(x + i NaN) = casinh(i NaN)    .... (1)

For a purely imaginary argument, which is where all this is coming from,
G.7 says

 	casinh(i NaN) = i asin(NaN) = i NaN

So, Eq(1) above is now

 	casinh(0 + i NaN) = 0 + i NaN        .... (2)

So, I believe that G.6.3.2 is wrong and should say

 	casinh(x + i NaN) = NaN + i NaN for finite x != 0

and an item to reflect Eq(2) above needs to be added.

Comments please?

Thanks - Damian


More information about the Cfp-interest mailing list