Why it doesn't matter if .9 repeating = 1

[Pimppeter2]

snip

Heh, I remember that thread.

 

[Steveh15]

Would somebody kindly point out where I'm going wrong, because it seems to me that I just proved that just over half = 1.

Your third line of math [ (5/10).5r = (5/10) ] more or less came out of nowhere and isn't true, that's why you just proved 0.55r = 1

 

[Aardvark]

Your third line of math [ (5/10).5r = (5/10) ] more or less came out of nowhere and isn't true, that's why you just proved 0.55r = 1

Bingo.

End of the day, round to the precision you need/laziness you are.

 

[slopeslider]

If you're talking theory, you can round if you're lazy. In practice, you round to the precision of the instruments you're working with.

Thank you. These can go to millionths of an inch in precision machining.

Parts with tolerances of 3 millionths of an inch keep your planes in the sky. Why don't we round? Cause then its not PRECISE, and you will experience massive amounts of DEATH.

Rounding .9r to 1 will result in an unmeasurable difference in the parts, down to the atomic level.

Then with whatever you're working with, you'd cut off the 9's in that spot. for for thousandths it would be .990, rounding doesn't carry up the number until it stops, only at the cutoff point.

That's not .9r, that's .999 or .9990
It's like saying pi=3.14 and not pi~3.14

Rounding to the accuracy of whatever you are measuring this number with is THE ACCEPTED method of the real world. Nice theory, but its that, a theory.

What's your point? And what theory did I assert? Are you talking about the whole '.9r is indistinguishable from 1' thing?
You've made slopeslider a confused boy :/

It's a theory that .9r is indistinguishable until you bring proof from the math community, not your notebook. To be frank, thinking that you are the first to postulate on this is arrogant. No offense, but do you think that in the near couple thousand years we have had complex math that nobody voiced this before you?

Who said I invented this? I already said I don't take advanced mathematics. I just thought of it recently is all.
Gravity is a theory also. As is evolution. Are you going to bring a counter-point or anything?

 

[Shru1kan]

snip

Who said I invented this? I already said I don't take advanced mathematics. I just thought of it recently is all.
Gravity is a theory also. As is evolution. Are you going to bring a counter-point or anything?

Accepted by all of the scientific and mathematical community?

But I'm done. Don't raise your hackles when I just had to be blunt for a minute to get my whole point across. A lot of things look cool on paper, I've had those moments too, but asking even my Calculus teacher some things... he can't explain how everything works in math either. The people that laid down the laws of mathematics were... well geniuses. And I'm sure this occurred to them, and they had a damn good explanation. I'm sure you could find someone who could tell you exactly why, but alas, that person is not me.

I'm sorry if I offended you. I meant to show a point, that is all.

 

[Scooter789]

May I direct you to here? http://qntm.org/?pointnine
(Don't worry, it's all text, no fancy flash or pictures to eat bandwidth.)

THIS.

I seriously can't believe that people are still fighting about this on the internet, or at all. It's been proven that .9r = 1 already.

 

[BuckminsterF]

Heisenburg's uncertainty theory says in practice, you can't know a value to an arbitrary (infinite) precision. In theory, however you can prove it equals one:

.9r = (9/10) + (9/100) + (9/1000)... so .9r- (1/10).9r = (9/10) = (9/10) + (9/100) + (9/1000)... - (9/100)+ (9/1000)...= (9/10) so (9/10).9r = (9/10) so .9r = 1 (divide by (9/10) on both sides)

.5r = (5/10) + (5/100) + (5/1000)... so .5r- (1/10).5r = (5/10) = (5/10) + (5/100) + (5/1000)... - (5/100)+ (5/1000)...= (5/10) so (5/10).5r = (5/10) so .5r = 1 (divide by (5/10) on both sides)

Would somebody kindly point out where I'm going wrong, because it seems to me that I just proved that just over half = 1.

.5r-(1/10).5r = (9/10).5r not (5/10).5r