From: <HIDDEN>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Inequality question
Date: Fri, 17 Apr 2009 19:02:01 +0000 (UTC)
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"Sprinceana " <> wrote in message <gsahll$72l$>...

> > ... snip ...
> > > 
> Can you help me please?

John outlined the solution for you in his original reply:

Sprinceana " <> wrote in message <gs9rs9$62a$>...
> I have the following inequality:
> -2<=648424649/617174649-154164883/3085873245*y+46354883/3085873245*x-74824961/15429366225*y*x-100/74529*x^2-100/74529*y^2<=2

No. You have a pair of inequalities, not a
single inequality relationship.

> Which is the best method to trace y=f(x) if we had an equation by type y-x=2

Define "trace" here. Do you wish to plot this
relationship? Why not use plot?

help plot
lookfor plot

The general scheme would seem trivial.

1. Generate a list of points x.
2. Compute y = f(x).
3. Delete those (x,y) pairs which fail to satisfy
the pair of inequality relationships given above.
4. Use plot(x,y,'-') on those remaining points.

... snip ...


All you need to do is write the "trivial"  MATLAB code.
Whats the problem?
What have you tried?
Where are you stuck?
What error messages do you get?