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Topic: Identifying a curve
Replies: 4   Last Post: Jan 11, 2008 4:58 AM

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David W. Cantrell

Posts: 827
Registered: 7/2/06
Re: Identifying a curve
Posted: Jan 10, 2008 5:49 PM
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"K. E. Pledger" <Ken.Pledger@MCS.VUW.AC.NZ> wrote:
> > Suppose you drew a circle of radius 200 mm on a piece
> > of paper with a compass and keeping the same centre
> > point you moved the pencil point in at five mm
> > increments so as to create ten circles each five mm
> > less radius to the one outside of it. Now you also
> > draw ten straight lines ( running up the page as it
> > were ) each five mm apart and position these lines so
> > as they cut through the circles with the extreme left
> > line being tangential with the inner circle and the
> > extreme right line being 45 mm to the right and of
> > course 45mm nearer the centre point of the circle.
> > What you end up with is a series of intersections
> > that when you connect with a line forms a curve.

> You seem to end up with 199 intersections. How do you intend to put a
> curve through them?

My guess, upon which my previous response was based, is that, for each
circle, he is considering only the two intersections closest to, but not
on, the horizontal line through the circles' centre.


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