ACOS logarithmic form

[Claudio L.]

(04-28-2016 06:44 PM)Dieter Wrote:  I wouldn't call this subtle, but obvious.

Well... wasn't so obvious to me, of course I'm well familiar with multivalued functions, but usually conventions dictate which value is the principal, and that's the end of it, calculations are straightforward and as long as you keep in the back of your mind that there's other solutions you can proceed without changes.
What got me is that using sqrt(z) vs. i*sqrt(-z) changes the selected branch only for some values, but not all.

(04-28-2016 06:44 PM)Dieter Wrote:  So it's actually OK to jump in and say "it's the same!". ;-)

Dieter

I knew somebody was going to... enjoy your moment of glory :-)

Now if I leave newRPL returning the other solution for ACOS... would you be the first one telling me "it's not the same! the other solution is the right one!" ?
I guess we'll never know... I made sure newRPL returns the expected value :-)