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convert fractional power to radical - DrD - 09-27-2017 03:04 PM
Can displayed results with fractional powers be shown with an equivalent radical (√) sign, instead? Is there a toggle for this?
-Dale-
RE: convert fractional power to radical - salvomic - 10-22-2017 05:41 PM
(09-27-2017 03:04 PM)DrD Wrote: Can displayed results with fractional powers be shown with an equivalent radical (√) sign, instead? Is there a toggle for this?
-Dale-
do you mean symbolic results?
I'm curious too how to obtain conversion, i.e., from 1/(x^3) into [3]√x or thing like that...
\( x^{\frac{1}{3}} \space \text{::} \sqrt[3]{x} \)
RE: convert fractional power to radical - DrD - 10-22-2017 06:39 PM
Yes. I haven't found a way to do that.
RE: convert fractional power to radical - webmasterpdx - 10-22-2017 10:00 PM
If it's in there it'd be in one of the algebraic expansion functions.
RE: convert fractional power to radical - webmasterpdx - 10-24-2017 02:49 AM
There is a way to do this in a program. You'd have to write a function as follows...
Convert the expression to a string. Then, wherever NTHROOT shows up in the string, substitute for dd NTHROOT x with x^(1/dd). Likewise, to go the other direction, search for x^(1/dd) and convert to dd NTHROOT x, still in string format.
Then call EXPR on the result.
Enjoy. Publish this if you write it :-)
RE: convert fractional power to radical - salvomic - 10-28-2017 03:15 PM
I'd like to have something like QPI (see here), but more general (also for x and variables) and ...built in in the CAS. Maybe someday... who knows?
Salvo
EDIT: however, for now, i.e., in Home QPI(x^(½)) returns 0, in CAS it, after some time, returns "Error: insufficient memory"... and no result.
RE: convert fractional power to radical - cyrille de brébisson - 10-30-2017 06:12 AM
Hello,
The problem is that this is a hard nut to crack and can yeild fairly long calculations.
Cyrille
RE: convert fractional power to radical - salvomic - 10-30-2017 07:53 AM
(10-30-2017 06:12 AM)cyrille de brébisson Wrote: Hello,
The problem is that this is a hard nut to crack and can yeild fairly long calculations.
Cyrille
Certainly, Cyrille, we understand that, however having radicals result would be useful.