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Re: How to use a returned pure function from say, Maximize



Hi Christoph,

we do not have any functions here, we have Root objects (look it up in 

the manual), that is, definite algebraic numbers. You may get a machine 

Number by using N[..], but you know this already.

The first number in your output is the maximum, the second gives the 

correponding x value.

hope this helps, Daniel



christophsk at gmail.com wrote:

> When I as Mathematica to maximize (over x) the expression

> 

> \frac{1}{2} \left(x \left(-2 \sqrt{1-x^2}+\sqrt{3-4 x (x+1)}+2\right)+

> \sqrt{1-x^2}\right)

> 

> I am returned this (after simplifying) - you can try it yourself,

> 

> {1/2 Root[

>    47972 - 156976 #1 + 144464 #1^2 + 616 #1^3 - 55340 #1^4 +

>      18312 #1^5 + 1316 #1^6 - 964 #1^7 - 47 #1^8 + 64 #1^9 +

>      16 #1^10 &, 5], {x ->

>    Root[-351 + 1440 #1 + 2520 #1^2 - 12672 #1^3 - 8192 #1^4 +

>       38528 #1^5 + 18176 #1^6 - 44032 #1^7 - 19968 #1^8 +

>       16384 #1^9 + 8192 #1^10 &, 5]}}

> 

> Bear in mind, this is just an example, but it illustrates the point.

> It is Ron Graham's Biggest Little Hexagon in case you want to look

> it up.

> 

> I can obviously recover the numerical value. But if I actually wanted

> to use this function, ie, substitute other expressions, manipulate it in some

> way, how do I do this?

> 

> More to the point, I've always been a bit confused how to make use of

> such a returned pure function.

> 

> Any help appreciated.

> 

> Thanks in advance.

> 





-- 



Daniel Huber

Metrohm Ltd.

Oberdorfstr. 68

CH-9100 Herisau

Tel. +41 71 353 8585, Fax +41 71 353 8907

E-Mail:<mailto:dh at metrohm.com>

Internet:<http://www.metrohm.com>




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