Re: PowerExpand, Apart, Simplify
- To: mathgroup at smc.vnet.net
- Subject: [mg5670] Re: [mg5654] PowerExpand, Apart, Simplify
- From: rhall2 at umbc.edu (hall robert)
- Date: Tue, 7 Jan 1997 11:22:46 -0500
- Organization: University of Maryland, Baltimore County
- Sender: owner-wri-mathgroup at wolfram.com
In article <5ap4kr$kv2 at dragonfly.wolfram.com>,
Allan Hayes <hay at haystack.demon.co.uk> wrote:
>"Lidar (Hamburger) dani" <dani at fh.huji.ac.il>
> [mg5654] PowerExpand, Apart, Simplify
> writes
>
>> ...I have not been able to find any way to make Mathematica
>>tell me that the following expression equals 1 (using the built-in
>>functions,that is):
>>
>>Sqrt[3 x^(4j)+x^(12j)]/(x^(2j)Sqrt[3 + x^(8j)])
>>(x,j real and positive)
>
>
>Dani:
>
>Factor//@Sqrt[3 x^(4j)+x^(12j)]/(x^(2j)Sqrt[3 + x^(8j)])
> 4 j 8 j
> Sqrt[x (3 + x )]
> ---------------------
> 2 j 8 j
> x Sqrt[3 + x ]
>
>PowerExpand[%]
> 1
>
>?//@
> MapAll[f, expr] or f //@ expr applies f to every
> subexpression in expr.
Using 2.2.2, MapAll isn't necessary.
In[6]:=
Sqrt[3 x^(4j)+x^(12j)]/(x^(2j)Sqrt[3 + x^(8j)])
Out[6]=
4 j 12 j
Sqrt[3 x + x ]
--------------------
2 j 8 j
x Sqrt[3 + x ]
And PowerExpand[] doesn't work.
In[7]:=
PowerExpand[%]
Out[7]=
4 j 12 j
Sqrt[3 x + x ]
--------------------
2 j 8 j
x Sqrt[3 + x ]
--
Bob Hall | "Know thyself? Absurd direction!
rhall2 at gl.umbc.edu | Bubbles bear no introspection." -Khushhal Khan Khatak