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Topic: It is a very bad idea and nothing less than stupid to define 1/3
= 0.333...

Replies: 31   Last Post: Oct 3, 2017 3:02 AM

 Messages: [ Previous | Next ]
 bursejan@gmail.com Posts: 5,511 Registered: 9/25/16
Re: It is a very bad idea and nothing less than stupid to define 1/3
= 0.333...

Posted: Oct 2, 2017 6:41 PM

Because pi is an incommensurable ratio, a Greek notion,
it can never by a rational number. But I don't know
whether they really considered pi already as such.

There is this story with pythagoras and sqrt(2)
irrational. But I am also loss what concerns the
"lost book by Fibonacci", I must have lost it as well:

Were ratios of incommensurable magnitudes
interpreted as irrational numbers prior to Fibonacci?
https://hsm.stackexchange.com/questions/5582/were-ratios-of-incommensurable-magnitudes-interpreted-as-irrational-numbers-prio/5585

Am Dienstag, 3. Oktober 2017 00:33:48 UTC+2 schrieb burs...@gmail.com:
> What do you want to fix? If pi is already there,
> than a 0-step process is sufficient, the process says:
>
> hi I am at pi
>
> Or if you want you can use a 1-step process, one
> that starts with Euler number e:
>
> hi I am at e
> now I add pi-e to myself
> hi I am at pi
>
> I guess you mean Q-series or something. Yes pi is
> irrational, no element from Q. And a Q-series will
> never hit pi on its way. Here is a proof:
>
> Proof: Assume a Q-series would hit pi on its way.
> Then there would be an index n, such that sn=pi,
> the partial sum up to n summands would equal pi.
>
> But each partial sum of a Q-series is from Q, and
> pi is not from Q, so we would get a contradiction
> saying pi is from Q, since it would be sn=pi.
>
> So by proof by contradiction the
> Q-series cannot hit pi.
>
>
> Am Montag, 2. Oktober 2017 23:32:25 UTC+2 schrieb netzweltler:

> > Am Montag, 2. Oktober 2017 22:09:44 UTC+2 schrieb burs...@gmail.com:
> > > Well this is probably the greatest nonsense somebody
> > > ever posted on sci.math. You know, you didn't say
> > > rational number line.
> > >
> > > So when it is the real number line, pi is of course
> > > there. There is of course a point on the real number
> > > line that is pi.

> >
> > It doesn't make sense to discuss the "number line" as long as the problem under discussion hasn't been fixed.
> >

> > >
> > > Am Montag, 2. Oktober 2017 19:54:44 UTC+2 schrieb netzweltler:

> > > > Yes. pi is already there and we can exactly locate its position on the number line, but you cannot locate a point on the number line representing pi if this point would be the result of a stepwise process - neither a finite process nor an infinite.

Date Subject Author
9/30/17 mitchrae3323@gmail.com
9/30/17 netzweltler
9/30/17 FromTheRafters
9/30/17 mitchrae3323@gmail.com
10/1/17 netzweltler
10/1/17 mitchrae3323@gmail.com
10/1/17 jsavard@ecn.ab.ca
10/1/17 mitchrae3323@gmail.com
10/2/17 netzweltler
10/2/17 Jim Burns
10/2/17 netzweltler
10/1/17 FromTheRafters
10/1/17 netzweltler
10/1/17 FromTheRafters
10/1/17 netzweltler
10/1/17 FromTheRafters
10/2/17 netzweltler
10/2/17 FromTheRafters
10/2/17 netzweltler
10/2/17 FromTheRafters
10/2/17 netzweltler
10/2/17 bursejan@gmail.com
10/2/17 Me
10/2/17 netzweltler
10/2/17 bursejan@gmail.com
10/2/17 bursejan@gmail.com
10/2/17 bursejan@gmail.com
10/3/17 netzweltler
10/2/17 FromTheRafters
10/2/17 jsavard@ecn.ab.ca
10/2/17 netzweltler