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Topic: Why do we need those real non-constructible numbers?
Replies: 1   Last Post: Nov 8, 2017 4:23 PM

 wolfgang.mueckenheim@hs-augsburg.de Posts: 3,394 Registered: 10/18/08
Re: Why do we need those real non-constructible numbers?
Posted: Nov 8, 2017 4:23 PM

Am Mittwoch, 8. November 2017 14:05:10 UTC+1 schrieb John Gabriel:
> On Wednesday, 8 November 2017 07:55:40 UTC-5, WM wrote:

> > Incommensurable means not simultaneously measurable with one and the same meter stick.
>
> No. Incommensurable means not measurable with ***ANY*** stick except itself!

The diagonal of a square can be measured by itself, by half of itself, by quarter of itself, and so on.
>
> > If you draw a unit circle you have constructed pi.
>
> Nope. You've only constructed the symptom of pi.

John, you call it the symptom, others call it a circle of length 2pi. That is not a deep question and not worthwile a discussion.

Regards, WM