February 21st, 2018, 09:46 AM  #21 
Global Moderator Joined: Oct 2008 From: London, Ontario, Canada  The Forest City Posts: 7,884 Thanks: 1088 Math Focus: Elementary mathematics and beyond 
Alright then  I'll reopen the thread but be advised that it will be strictly moderated. 
February 21st, 2018, 10:26 AM  #22 
Senior Member Joined: Aug 2012 Posts: 2,098 Thanks: 602  Greg1313, What puzzles me is why you let FLT and Collatz threads go on for months but react so strongly to this one particular poster. If the socalled anticrank standards were more evenly enforced, they would not seem so unfair and directed at one single individual.

February 21st, 2018, 11:03 AM  #23 
Global Moderator Joined: Oct 2008 From: London, Ontario, Canada  The Forest City Posts: 7,884 Thanks: 1088 Math Focus: Elementary mathematics and beyond 
The FLT and Collatz threads are following the rules. The guidelines I've recently posted are being followed so if someone thinks they have an elementary proof of FLT/Collatz there's really not much I can do. zylo remains congenial but is given to ignoring input from other members and making obscure references to other posts. As I said the forums will be strictly moderated when it comes to things of this sort, from here on in. I will give some credibility to your concern  I was somewhat heavyhanded with zylo, but only because I think he could do so much better. I've been impressed by several posts of his. Thank you for your concern, greg1313 
February 22nd, 2018, 07:01 AM  #24 
Senior Member Joined: Mar 2015 From: New Jersey Posts: 1,603 Thanks: 115  1) What is a real number? a) Cut of the rational numbers b) Point on a line c) Infinite decimal 2) What is limit of a function? $\displaystyle \lim_{x\rightarrow a}$f(x) =A if, given any $\displaystyle \varepsilon$, $\displaystyle \delta$ exists st f(x)A < $\displaystyle \varepsilon$ when xa< $\displaystyle \delta$ nplace decimals in [0,1) can be arranged in numerical order, which makes them countable for all n (cardinality of real numbers), and therefore countable in any subinterval (cardinality of an interval}. Bijective map of line to a finite surface : Divide the surface into nstrips. Map [0,1) to CL of first strip, [1,0) to CL of second strip, ......, [n1,n) to center line of nth strip. Let n $\displaystyle \rightarrow$ approach infinity (induction). Bijective map of line to finite volume: Divide the volume into n^2 square rods. Map [0,1) to CL of first rod, etc. Let n $\displaystyle \rightarrow$ infinity. Last edited by zylo; February 22nd, 2018 at 07:12 AM. Reason: change intervl to interval and add space 
February 22nd, 2018, 09:06 AM  #25 
Global Moderator Joined: Dec 2006 Posts: 19,957 Thanks: 1844 
Please explain what you mean by "nplace decimal". Is there some other type of decimal that isn't an nplace decimal?

February 22nd, 2018, 01:23 PM  #26 
Math Team Joined: Jan 2015 From: Alabama Posts: 3,261 Thanks: 894  If, by "nplace decimals" you mean those decimal that have n decimal places (with only '0' after) then yes, for every n they are countable. However, the collection of all such "nplace decimals", for all n, is precisely the set of all rational numbers, not the real numbers. $\pi$, for example, is not in that set because there is no n for which $\pi$ is a "nplace decimal".

February 22nd, 2018, 01:54 PM  #27 
Global Moderator Joined: Dec 2006 Posts: 19,957 Thanks: 1844  
February 22nd, 2018, 05:23 PM  #28  
Math Team Joined: Dec 2013 From: Colombia Posts: 7,509 Thanks: 2514 Math Focus: Mainly analysis and algebra  Quote:
Here we go again. Same old nonsense, no attempt to understand why it's nonsense. I'm not going to bother explaining again. Neither do I care what nonsense you are basing on it. Suffice to say that none of it is mathematics.  
February 24th, 2018, 09:18 AM  #29 
Math Team Joined: Jan 2015 From: Alabama Posts: 3,261 Thanks: 894  Ouch! Yes, you are right of course. Thanks for the correction. But they certainly are not all real numbers!
Last edited by skipjack; February 24th, 2018 at 11:28 AM. 

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