Re: Cube root of -1 and 1
- To: mathgroup at smc.vnet.net
- Subject: [mg90891] Re: Cube root of -1 and 1
- From: Steven Siew <stevensiew2 at gmail.com>
- Date: Mon, 28 Jul 2008 07:53:23 -0400 (EDT)
- References: <g6h5fm$h26$1@smc.vnet.net>
On Jul 27, 4:44 pm, Bob F <deepyog... at gmail.com> wrote:
> Could someone explain why Mathematica evaluates these so differently?
>
Try this
Table[(Sqrt[36]-n)^(1/3),{n,0,7}]
(1)^(1/3)
(0)^(1/3)
The short answer is :
One to the power of anything is one
Zero to the power of anything (non-zero) is zero.
Zero to the power of zero is Indeterminate.
Steven Siew
> In[53]:=
>
> (Sqrt[36] - 7)^(1/3)
> (Sqrt[36] - 5)^(1/3)
>
> Out[53]= (-1)^(1/3)
>
> Out[54]= 1
>
> In other words why isn't (-1)^1/3 expressed as -1 ??
>
> Thanks...
>
> -Bob