# .9 Repeating = 1 YES -or- NO

## Does .9 Repeating equal to 1?   116 members have voted

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ambient

look at the title of the forum .9 Repeating = 1 YES -or- NO

If you agree on a comment that in mathematics this is true, then you are answering a math question in terms of something other than math by saying it isn't true, so I guess no one can prove it to you, expecialy when you ignore all the proofs, everything I and others say, and every comment I make about the actual topic at hand.

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I can no longer be bothered to use my big flashy words, as you not only seem to be confused, but also can not comprehend the logic of Mr. Spock and the rest of the world. Tune in next time, for another exciting edition of,

R002092 is no longer listening

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Obi Wong

ummmmm

if it's like a limit that's like so close to one that it actually IS one then yes

0.999999 forever is pretty much one

but in actuality, it's not because it's just a repeating number that goes on forever

it's like have 1/(something that's approaching infinity) the number is so small because it's being divided by something that's so big that it's actually zero...

..or something like that

i don't really pay much attention in calc :pinch:

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zhangm

lol, this is funny.

Simple geometrical proof that .9 recurring does not equal 1.

On a simple graph, draw a line with angle of .9 recurring degrees.

Now draw another line with angle of 1 degrees.

Are these lines parallel or do they intersect at some point?

johngalt

Dear God.

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futb0l

:D i just round it up ... LOL

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oldmate15
:D i just round it up ... LOL

hey now THATS more like it :)

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aldo

It is.

Not only that - you cannot prove it without algebra, since our brains can not work with infinity. Our brains always expect to have an end of something.

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Peter Griffin

NOT A CHANCE..........crazy folks voting yes.............try not to skip math class from now on.

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Toxicfume

In theory I can see and accept that 0.9999.... = 1 since: what could you add to that 0.999... to get it to 1? 0.00000.........on and on....until it reaches 1 -right? But 1 never comes here, cause it's infinite 0s, thus 0.9999... = 1

But when I think practically, lets say we draw the thinnest straight line possible representing 1, and then we draw another thinnest line posible that is bending towards one and it goes on 0.9999..... it will approach 1 but it just would NEVER reach 1. It's either that or I just cannot comprehend that scenario

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cesardrgn

Dazzla is right...

Tech_8356

nope

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dickie
x = 0.9999...

10x = 9.9999...

10x - x = 9x

9.9999... - 0.9999... = 9

9 = 9x

1 = x = 0.9999...

thats crazy dazzle..

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Elliott

Dazzla is right. :yes:

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Blodia
x = 0.9999...

10x = 9.9999...

10x - x = 9x

9.9999... - 0.9999... = 9

9 = 9x

1 = x = 0.9999...

Ok I somewhat understand your proof, but what happened to the 9x? Shouldnt that turn into 9 * .9999 repeating? You just droped the x for no apparant reason. Another thing, theres a difference between EXACT values, and rounded values. Exact values stay as fractions, and therefor if you leave everthing in EXACT form, you cant make it equal to 10. You were only accomplishing it by using rounded values. 0.999 repeating is still a rounded value because it never reaches the end.

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Ravager
10x = 9.9999...

10x - x = 9x

9.9999... - 0.9999... = 9

9 = 9x

1 = x = 0.9999...

This is a flaw of the decimal system.

For example.

1/3 = 0.333333

(1/3) * 3 = 1

0.3333 * 3 = 0.999999

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clonk
I think the problem is you guys are trying to solve a calculus problem with plain algebra, your ignoring the fact the limit of something doesn't equal what it approaches. That's just simple Calculus I.

I totally agree here OPaul. These people who are trying to claim that .99999999999999... equals 1 obviously have not studied Calculus in the slightest. Or if they have they didn't learn a thing :)

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clonk

Ok, I've decided to go ahead and show all you .9999999 = 1 believers that you are flat out wrong.

I will be using Calculus to prove this, more specifically limits.

In this instance we are dealing with a Limit Involving Infinity. When dealing with infinity it is important to remember infinity does not represent a real number. We use infinity to describe the behavior of a function ( F(x) ) when the values in its domain and range outgrow all finite bounds. Since we are debating whether .999999... = 1 the function 1 / ( x - 1 ) will be useful for illustrating that is it not. Refer to my attached notes I have prepared on this below.

Please note I assume you have an understanding of this material already, I'm not here to teach you Calc. If any other Calc enlightened souls have any corrections or anything to add feel free to do so.

Edited by clonk
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clonk

Here is the Journal Note File of the above JPEG if anyone is interested in having it.

You'll need the Journal Viewer to open it.

Limits_involving_Infinity.jnt

Edited by clonk
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Jean-Claude Van Damme

+/- 75% voted NO?

LMAO

Man, those people better not apply for any jobs in math. Especially those that designed weird ass methods trying to disprove it.

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clonk
+/- 75% voted NO?

LMAO

Man, those people better not apply for any jobs in math. Especially those that designed weird ass methods trying to disprove it.

Do you even know what you are talking about? What is wrong with the method I used to prove this?

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Evolution
Ok, I've decided to go ahead and show all you .9999999 = 1 believers that you are flat out wrong.

I will be using Calculus to prove this, more specifically limits.

In this instance we are dealing with a Limit Involving Infinity.? When dealing with infinity it is important to remember infinity does not represent a real number.? We use infinity to describe the behavior of a function ( F(x) ) when the values in its domain and range outgrow all finite bounds.? Since we are debating whether .999999... = 1 the function 1 / ( x - 1 ) will be useful for illustrating that is it not.? Refer to my attached notes I have prepared on this below.

Please note I assume you have an understanding of this material already, I'm not here to teach you Calc.? If any other Calc enlightened souls have any corrections or anything to add feel free to do so.

But aren't infinite repeating numbers dealing with infinity? Then again, I find it interesting how people, in previous posts, tend to use infinity casually like any other number...What's next, going on to prove 0=1 ?

BTW I do agree that it doesn't =1. Although Dazla's logic is correct, his assumptions are not.

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dL

0.9 repeating does not equal to 1 .. it will keep on going very very close to 1 but it'll never get there.. just like those asymtotes on the graph..

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Evolution

All this is proving is that, there is an error in your understanding of mathematics Proxy. It's best to just stay away from infinity until you have a proper one :)

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SMeK

well forget the maths

look at the damn number

does anyone see a bloomin 1 in that number?

no.

end of discussion