Advertisement
 

Membership

 

Advertisement

 

Latest StarCraft VODs

» View all VODs (201)

Advertisement

 
Forums \ General forum \ Math question!
1, 2, 3, 4, 5 
Information
Big stars represents five levels - This user is on level 7
Small stars represents one level - This user is on level 7Small stars represents one level - This user is on level 7
ImCh1efPeasant
Math question! (14753 reads, 93 replies, 1 year ago)
I had a discussion with some friends (kinda nerdy discussion =d)

They thought that 9.99999999999999999999999999...=1
and I said that 9.99999999999999999999999... =/= 1

can any1 try to prove to me that I'm indeed wrong and that 9.99999999999999999999999999...=1
?

note: 9.99999999999999999999999999... means infinity amount of 9's
This post was edited by a forum moderator @ 1 year ago
Quote  
 

1 year ago
#1
Small stars represents one level - This user is on level 3Small stars represents one level - This user is on level 3Small stars represents one level - This user is on level 3
37927
9.99999999999999999999999999...=1

it does not equal (nearly one), it equales nearly ten.

and no, that is not 10, it is equal the number it says, but people often cuz of lazyness write it like a whole number. Those difference is only important to people who are meticulous, and one more thing where it matters could be in atom physics or something really important, precise etc.
I like trains.
This post was edited by its author @ 1 year ago
Quote  

1 year ago
#2
Small stars represents one level - This user is on level 4Small stars represents one level - This user is on level 4Small stars represents one level - This user is on level 4Small stars represents one level - This user is on level 4
KoyomiSandwich
#1 is right ... It's nearer to 10 ... @_@

If you're talking about 0.9999999999999.. They will never be equal
Any game can be won with the power of turtle!
This post was edited by its author @ 1 year ago
Quote  

1 year ago
#3
Big stars represents five levels - This user is on level 5
AnubiA.DemoniC
0.9999999.. will never be = 1, this goes on for an eternity however; you will always be missing that little part, which would make it 1.
I assume you mean 0.99.... and not 9.99 because then the difference is big Oo
Can't really point it out, other than in THEORY it will be different, but in the world (Atleast from what I know of) - noone can say "here, we need 0.99999999999999... gram of this in, while we need 1.00000000000... gram of this!"

TL:DR - In theory it's different, but practic use, it is not (well it is, but then again; leads back to theory)
Nerf Scissors, rocks are fine. - Paper
Quote  

1 year ago
#4
rEd-
Nope they are nvr equal-
0.99999999.... x times < 1
9.99999999.... x times < 10 (Im assuming its one of the 2 cases i mentioned coz ur case doesn make sense..:)
In both cases 1 and 10 they are greater by exactly 0.0000.....(x-1) times1

Ps- 'x' is a variable wherein each case it refers to the number of digits after the decimal point
In the last case where i explained The calulated difference between them, '1' at the end of the result is the xth number after the decimal point(Hence zeroes upto x-1 times and then 1)
Example - If x = 5
0.99999(Five 9's)
Then 1 > o.99999 by 0.00001 (x-1 = 4 Therefore 4 zereos then 1)
Hence in ur case like u said infinite 9's where x= infinity,the differnce btwn the numbers is o.oo...(Infinity-1)1

Sry if i made it a little more complicated then it shud be..:D..i cud put it btr on paper using math terms but i dun kno how to put calculatr font here so i did what i could..Hope this answered your question
This post was edited by its author @ 1 year ago
Quote  

1 year ago
#5
vlovo.792
its important when you talk about pricise things or about realy big amounts. like john has 0.999999 trillion dollars.

bob says, wow he has trillion dollars.

bob just miscounted by a million dollars(or something like that, i didnt actually look)
Quote  

1 year ago
#6
Big stars represents five levels - This user is on level 7
Small stars represents one level - This user is on level 7Small stars represents one level - This user is on level 7
anatase
Blizzard for the april fool some years ago did "prove" that 0.99999999999=1

but it was an april fool;).


In fact it won't ever be equal to 1
Holydamned sh**
Quote  

1 year ago
#7
Small stars represents one level - This user is on level 3Small stars represents one level - This user is on level 3Small stars represents one level - This user is on level 3
Jizzus
Instead of proving you wrong, ICP, don't you want a confirmation that you're actually right? :P
Quote  

1 year ago
#8
Small stars represents one level - This user is on level 4Small stars represents one level - This user is on level 4Small stars represents one level - This user is on level 4Small stars represents one level - This user is on level 4
Brewsto
Infinities are hard to understand.

Here is why your friend(s) is/are right.

x=0.999999...
10x=9.9999...
10x-x=9.999...-0.9999...
9x=9
x=1
Quote  

1 year ago
#9
Small stars represents one level - This user is on level 2Small stars represents one level - This user is on level 2
GigaGenesis
^ your mistake is that [infinity]-[infinity] doesn't make sense so 9.999...-0.999...=/=9
Quote  

1 year ago
#10
Small stars represents one level - This user is on level 3Small stars represents one level - This user is on level 3Small stars represents one level - This user is on level 3
Jizzus
2010-09-01 22:08, Brewsto wrote:
Infinities are hard to understand.

Here is why your friend(s) is/are right.

x=0.999999...
10x=9.9999...
10x-x=9.999...-0.9999...
9x=9
x=1


You owe that misconception to ignorant academics.
Quote  

1 year ago
#11
Small stars represents one level - This user is on level 4Small stars represents one level - This user is on level 4Small stars represents one level - This user is on level 4Small stars represents one level - This user is on level 4
Brewsto
#10 You owe that misconception to brain failure. Quote what you think I have wrong on my previous post

#9 For you baby
This post was edited by its author @ 1 year ago
Quote  

1 year ago
#12
Small stars represents one level - This user is on level 3Small stars represents one level - This user is on level 3Small stars represents one level - This user is on level 3
gt2slurp
#8 is totally right ^^

0.9999... really =1

You can't think about "the last 9", the last 9 of a periodic number does not exist. You have to think about it like limits when the number of nine tend to infinity.

x=0.999999...
10x=9.9999...
10x-x=9.999...-0.9999...
9x=9
x=1

This proof is a little straightforward but still correct. This one exist too:

1/3=0.333...
3 x 1/3 = 0.999...
1=0.999...
GtZslurp.behemoth NA server
This post was edited by its author @ 1 year ago
Quote  

1 year ago
#13
Small stars represents one level - This user is on level 2Small stars represents one level - This user is on level 2
1chigo
they are in fact equal 0.9999..=1.

i guess the simplest way to explain it and understand it, is this:

9 * (1/9) = 9 * (0.111...) = 0.99999...

alternatively:

9 * (1/9) = 9/9 = 1
Quote  

1 year ago
#14
Small stars represents one level - This user is on level 2Small stars represents one level - This user is on level 2
tfarcraw
nice 1! =.=
Quote  

1 year ago
#15
Small stars represents one level - This user is on level 4Small stars represents one level - This user is on level 4Small stars represents one level - This user is on level 4Small stars represents one level - This user is on level 4
DoomsVille
http://lmgtfy.com/?q=does+0.9999+equal+1

Yes it is 1.
Quote  

1 year ago
#16
Small stars represents one level - This user is on level 3Small stars represents one level - This user is on level 3Small stars represents one level - This user is on level 3
Jizzus
Damn, I thought I'll save myself from the trouble of typing all that... Anyway, here goes the reason why this is a misconception. I hope I can make it comprehensible enough without going into the details.

First, I have to comment on the nature of infinity why infinity and infinite "numbers" aren't actual numbers. We assume they are but reality says otherwise.

If I (infinity) + 1 = I then we could also say that I - 2 = I.

Where's the problem?

I+1=I
I-2=I

=> 1=-2

This is just another way to abuse arithmetic principles and it's only possible, because the concept of infinity came long after 1+1=2. That's why arithmetic can't account for it. Some people, questioning the possibility of having an uncertainty in maths, look for rational explanations.

I believe the explanation physics has to offer is much more beautiful, but it won't make much sense to you (or at least I don't know how to make it short and simple enough for you to understand :<).
Quote  

1 year ago
#17
Small stars represents one level - This user is on level 2Small stars represents one level - This user is on level 2
Alkatraz
#16 get your facts straight

I + 1 != I
Quote  

1 year ago
#18
Big stars represents five levels - This user is on level 12 Big stars represents five levels - This user is on level 12
Small stars represents one level - This user is on level 12Small stars represents one level - This user is on level 12
Pulimuli
this is how i would say it "0.99999999...." is not equal to 1, stop being retarded"

edit: also, slap them in the face
This post was edited by its author @ 1 year ago
Quote  

1 year ago
#19
Small stars represents one level - This user is on level 3Small stars represents one level - This user is on level 3Small stars represents one level - This user is on level 3
Jizzus
2010-09-01 23:06, Alkatraz wrote:
#16 get your facts straight

I + 1 != I


So, when trying to give a simple answer, I have to explain the concept of the continuum hypothesis?
Quote  

1 year ago
#20
Shaid
2010-09-01 22:53, Jizzus wrote:
Damn, I thought I'll save myself from the trouble of typing all that...

I believe the explanation physics has to offer is much more beautiful, but it won't make much sense to you (or at least I don't know how to make it short and simple enough for you to understand :<).


As a Physicist I'd love to hear this explanation.

.9999(...)=1 is a math question, not a physics, nor philosophical one as it is mathematics which defines what the equal (=) symbol means. Given the set of real numbers, the multiplication operator (*), and a uniqueness theorem we can easily show that as defined by mathematics .999(...) is in fact the same real number as 1.
For any 3 real numbers A,B, and C (excluding 0 of course) If, A*B=C*B then A=C (this holds true for any field) so given that the set of real numbers form a field under +/* and the fact that .9999999(...)*1/9 = .1111111111(...)=1*1/9
we have
.9999999(...)*1/9 = 1*1/9
.9999999(...)= 1

QED
Quote  

1, 2, 3, 4, 5 

Forum post
  • Do to others what you would have them do to you.
  • Do not judge so that you will not be judged.
    » Read posting rules in detail

    Reminder: IP-addresses for the comments are saved. Offensive posts will be censored. Repeated offense will result in a warning and/or a temporary account lockdown.
    • Math question! \ Reply
    To submit a post, you have to be a registred member. Register an account below the title 'Membership' in the left menu.

    » Top of the page