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Topic: How to solve this equation?
Replies: 6   Last Post: Apr 18, 2012 4:56 PM

 Messages: [ Previous | Next ]
 networm Posts: 327 Registered: 10/6/05
Re: How to solve this equation?
Posted: Apr 18, 2012 3:30 PM

On Apr 18, 2:27 pm, Lucy <comtech....@gmail.com> wrote:
> On Apr 18, 1:00 pm, Lucy <comtech....@gmail.com> wrote:
>
>
>
>
>

> > On Apr 18, 12:37 pm, James Waldby <n...@valid.invalid> wrote:
>
> > > On Wed, 18 Apr 2012 10:09:02 -0700, Michael wrote:
> > > > I have sum(w_i, i from 1 to n)=1 given,
>
> > > > and also I am given a set of numbers e_i, i from 1 to n.
>
> > > > Now I need to find a number u, such that
>
> > > > sum(w_i/(u - e_i)^2, i from 1 to n) ...
>
> > > > My questions are: are there systematic way of finding all possible
> > > > solutions u?

>
> > > You didn't state any condition on u (except perhaps implying it's not
> > > equal to any e_i).  State an equation before asking for solutions.  Also
> > > clarify if w_i are given (besides e_i) and if u is the only unknown.

>
> > > > And is the number of solution related to n?
>
> > > > I am thinking of maybe for n=2, the number of solutions u is 1?
>
> > > > And for general n, the number of solutions u is n-1?
>
> > > --
> > > jiw

>
> > yes,u is unconstrained... the only unknown...- Hide quoted text -
>
> > - Show quoted text -
>
> u is unconstrained... all the rest are given...
>
> and yes, w_i >=0 for all i...
>
> Thank yuo!- Hide quoted text -
>
> - Show quoted text -

Now I need to find a number u, such that

sum(w_i/(u - e_i)^2, i from 1 to n) = 1.

And I am looking for real numbers u...

Date Subject Author
4/18/12 Michael
4/18/12 James Waldby
4/18/12 networm
4/18/12 networm
4/18/12 networm
4/18/12 quasi
4/18/12 Dan Cass