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May 18 2010 09:29pm
Quote (CPK001 @ 18 May 2010 21:10)
so if we times that decimal number by 7, then it should = 1?


yes

This post was edited by J_B on May 18 2010 09:29pm
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May 18 2010 09:46pm
Quote (CPK001 @ May 19 2010 03:10am)
so if we times that decimal number by 7, then it should = 1?


Try it with a calculator.

Notice how the more decimal places you use, the closer to 1 you get.
For example, .1*7 = .7,
.14*7 = .98 (ahh much closer),
.142*7 = .994, etc etc.
The only way it would equal *exactly* 1 is if you could take .142857142857.... (repeating infinitely) and multiply it by 7. However it is technically impossible to use a calculator to do such a thing, since we cannot actually type out the decimal form of 1/7 since it goes on forever.

But to answer your question more simply, of course it equals 1: .142857... and 1/7 are *the same number* so they behave in exactly the same manner under arithmetic.
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May 18 2010 10:00pm
Quote (chone @ May 19 2010 01:46pm)
Try it with a calculator.

Notice how the more decimal places you use, the closer to 1 you get.
For example, .1*7 = .7,
.14*7 = .98 (ahh much closer),
.142*7 = .994, etc etc.
The only way it would equal *exactly* 1 is if you could take .142857142857.... (repeating infinitely) and multiply it by 7. However it is technically impossible to use a calculator to do such a thing, since we cannot actually type out the decimal form of 1/7 since it goes on forever.

But to answer your question more simply, of course it equals 1: .142857... and 1/7 are *the same number* so they behave in exactly the same manner under arithmetic.


Just that 1/7 makes it a lot quicker than to write it down the other way?
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May 18 2010 10:35pm
Quote (Kahl4Prez @ Apr 11 2010 10:45am)
this is just for fun so i can link a friend to this later on,

i just like this argument

so lets have some fun with ez math

does .99999.... = 1 ?

i can do many proofs of this lets see how many i can get here


Yes it does. .999999.... going to infinity gets so infinately close to one that it is, for all purposes, one. I could post some proofs but honestly, I dun fee like it lol
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May 18 2010 11:14pm
Quote (Yankzfan @ 18 May 2010 22:35)
Yes it does. .999999.... going to infinity gets so infinately close to one that it is, for all purposes, one. I could post some proofs but honestly, I dun fee like it lol


not quite
it's not arbitrarily close to 1
it is one
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May 19 2010 12:47am
Quote (CPK001 @ May 19 2010 04:00am)
Just that 1/7 makes it a lot quicker than to write it down the other way?


Sure, you can think of it like that. But there's more to it than just that. There's a matter of precision. If you're working on a problem and you come across the quantity 1/2, you can surely write it as 0.5 - not just because it's short/easy to write down, but also because there's no confusion about what you're talking about. 1/2 is 0.5. ANY decimal representation that you write down of 1/7 will be an estimation: 0.1428 is very close to 1/7, but they aren't the same. So if you want to be precise, use 1/7.

Quote (Yankzfan @ May 19 2010 04:35am)
Yes it does. .999999.... going to infinity gets so infinately close to one that it is, for all purposes, one. I could post some proofs but honestly, I dun fee like it lol


There's no such thing as "infinitely close" in the real numbers (this is a consequence of the Archimedean property). So no, .999... is not infinitely close to 1. It IS one.
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May 19 2010 02:42am
Quote (Kahl4Prez @ Apr 11 2010 02:45am)
this is just for fun so i can link a friend to this later on,

i just like this argument

so lets have some fun with ez math

does .99999.... =  1  ?

i can do many proofs of this lets see how many i can get here


No.
.9 bar will always be one fraction from a whole
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May 19 2010 06:30am
Let's put it this way.
You have a cake.
Someone asks for 0.999... of the cake.
No matter how much you cut off, regardless of how small it is, you would have cut off too much.
The only way to cut off exactly the right amount would be to cut off nothing at all.
Also, if someone asks for 0.000... 1 of a cake, then no matter how much you give him you would have given him too much.
The only way to give 0.000... 1 of a cake is to give nothing at all.
Therefore 0.999... = 1 and 0.000... 1 = 0, so those of you who are saying that you have to add 0.000... 1 to 0.999... to make 1, you are really just adding 0 to 1 which does nothing.
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May 19 2010 08:25am
Oh crab.

But this must live.
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May 19 2010 01:27pm
Quote (Hammer_Hdin @ May 19 2010 12:30pm)

Therefore 0.999... = 1 and 0.000... 1 = 0


You're right about 0.999... = 1, but 0.000...1 is not a real number. It is not equal to zero.

This thread will fucking THRIVE as long as retards keep posting...because angry math nerds like myself will continue to tell them they are retarded.
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