Advanced Graphing App

[Nigel (UK)]

(05-18-2015 12:18 AM)lrdheat Wrote:  In function app, 3 Root (x-2) plots fine. In advanced graphing app, only the part of the graph where x>2 plots. Same for (x-2)^1/3. I was looking to find the inflection point of the function in the advanced graphing app (which happens to occur at x=2). Is there a way to get the complete plot of this function in tha advanced graphing app?

The reason it doesn't work with powers (e.g., (x-2)^(1/3)) is that a fractional power of a negative number is in general complex. If you try working out (-2)^1/3 from the keyboard (in Home) you'll either get an error or a complex result, if "Allow complex results from real input" is ticked. This is as it should be: forcing (-2)^(1/3) to be real would mean an extra discontinuity (a cut) in the function in the complex plane.

I thought that the nthroot function (e.g., 3 nthroot (-2)) was intended to get around this. It gives a real result in the Home screen, but not in the Advanced Function app - a bug, perhaps?

Apologies if this is obvious!

Nigel (UK)