Post: Mathematical Proof that 0.999...=1
10-16-2010, 03:40 AM #1
elfmotat
Rᵤᵥ - ½gᵤᵥR ∝ Tᵤᵥ
(adsbygoogle = window.adsbygoogle || []).push({}); I will prove that 1=0.999999... This one IS NOT a troll (no sneaky tricks like the last one i.e. dividing by zero).

The Fractions Proof

This one requires little to no math knowledge. Note that You must login or register to view this content. represents 0.999999...

One third is equal to 0.33333...

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Three times one third is equal to 1:

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Three times 0.33333... is equal to 0.999999...

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Therefore 1=0.999999...

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The Infinite Series Proof

A number with a repeating decimal can be represented as a sum of an infinite series:

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The formula to find the value of an infinite series where |r|<1 is as follows:

S is the sum, t1 is the first term in the series, and r is the rate.

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Therefore:

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The Algebraic Proof

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Multiply both sides by 10 (remember that when you multiply by ten it shifts the decimal place to the right by one place):

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Subtract x=0.9999... from both sides:

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Simplify:

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Divide by 9:

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The Midpoint Proof

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What is the midpoint (average) between a and b? The formula to find m where m is the midpoint is:

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Using the values for a and b:

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You can use long division to divide 1.9999... by 2 to get m=0.99999...

Since the midpoint between the two points IS one of the two points, the two points MUST be equal. If you are unconvinced that this is true, you could say from the information that:

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Multiply both sides by two:

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Subtract b from both sides:

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Simplify:

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Substituting numerical values:

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The following 3 users say thank you to elfmotat for this useful post:

CRaZyY, Dreamy, IDontbreak
10-16-2010, 03:45 AM #2
SuperYuper
Vault dweller
One third is equal to .3 repeating, not 0.33333 Happy...
10-16-2010, 03:46 AM #3
my head hurts lol
10-16-2010, 03:47 AM #4
elfmotat
Rᵤᵥ - ½gᵤᵥR ∝ Tᵤᵥ
Originally posted by SuperYuper View Post
One third equal to .3 repeating, not 0.33333 Happy...


.33333... denotes .3 with repeating 3's. Notice the ...? I'm really not sure how you could have missed that, unless you're trolling.
10-16-2010, 03:55 AM #5
SuperYuper
Vault dweller
Originally posted by elfmotat View Post
.33333... denotes .3 with repeating 3's. Notice the ...? I'm really not sure how you could have missed that, unless you're trolling.

I'm not trolling. Didn't we kind of learn this in grade school that one third is equal to .33333... and decimals aren't completely accurate?
10-16-2010, 04:07 AM #6
Dopey
NGU :/
Am i the only one having problems seeing the images?
10-16-2010, 04:10 AM #7
*SaM707*
Th3 On3 & OnLy
What's next, 5,000,000 = 1 huh

---------- Post added at 09:10 PM ---------- Previous post was at 09:09 PM ----------

Originally posted by Dopey View Post
Am i the only one having problems seeing the images?


Nope I can't see them either
10-16-2010, 04:11 AM #8
jovero
Raiders
I can't see the images either.
10-16-2010, 04:11 AM #9
elfmotat
Rᵤᵥ - ½gᵤᵥR ∝ Tᵤᵥ
Originally posted by SuperYuper View Post
I'm not trolling. Didn't we kind of learn this in grade school that one third is equal to .33333... and decimals aren't completely accurate?


What do you mean decimals aren't accurate? Of course they are. The fact that the digit is repeated ad infinitum makes it 100% accurate. If I rounded the decimal then it wouldn't be accurate, but I didn't.
10-16-2010, 04:21 AM #10
SuperYuper
Vault dweller
Originally posted by SaM707
What's next, 5,000,000 = 1 huh


Proof that 5,000,000=1

5,000,000 x 0=0
1x0=0

5,000,000=1

The following user thanked SuperYuper for this useful post:

the stuff

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