0.999 exactly equal to 1?

Alright I read on the internet awhile ago that 0.999 is somehow exactly equal to 1. This may sound retarded (thats what I thought) but check out this:

Let X= 0.999
10X = 9.999
10X - 1X = 9.999- 1X
9X=9
which means X = 1

Look it over a few times before saying Im wrong.

 

?? 0.999 * 10 = 9.99, not 9.999 ... then 9.99 - 1X = 9.99 - 0.999 = 8.991, not 9.

 

i don't like math...numbers are the devils doing

 

It's not litteraly "0.999" it's "0.999 repeating." so 0.999*10=9.999 and 0.999*100=99.999. I don't think you can show repeating decimals on a computer
Because you can never subtract a small enough value from 1 to equal 0.99999 repeating, it's said there is no difference between them. It's one of the wackier parts of math.

 

search it on google theres lots of websites that "prove" it

 

Right, 9.9999... repeating does equal 1. Nevermind.

 

^ I cant tell if your being sarcastic or not

 

Me, nope ... it is true. BTW, thanks for sharing because it is easy to forget it and it is an interesting little math thing.
Peace and Love,
Ryvr

 

1 is not equal to 9.999...
even if you put like 500 nines after the point and do the operation mentioned in the very first post you will still find that the result is never equal to 1 no matter how many nines you put.

 

9.999 - 1X is unsolvable unless there is an answer to the equation, without an answer you can't find a solution to X

you can't just say that 9.999 -1X makes X =1

 

if you fall for this you should be shot

 

omg, that is retarded. ok. heres disproof.
Let X = .999
- multipy both sides by 10 for some dumb ass reason
10*X = 10 * .999
-subtract 1X for some other dumb ass reason
10*X - 1X = 10*.999 - 1*.999 (since X =.999)
-subtract like terms to simplify
9X = 9*.999
- divide both sides by 9 to isolate x
X = .999

which is exactly what you started with, as you would expect. anytime you perform the same act on both sides of an equal sign you have done nothing. thanks.

 

9.999-0.999=9

 

ok, theres a much simpler way to prove this


0.333 + 0.666 = 0.999

0.333 = 1/3

0.666 = 2/3

1/3 + 2/3 = 1

0.999 = 1

 

X acts as either a variable or a constant, but it cannot be both simultaneously.

Let X= 0.999
10X = 9.999
10X - 1X = 9.999- 1X (can't treat 1X as a variable on one side and a constant on the other) thus,
10X - 0.999=9
10X= 9.999
which means X = 0.999

 

Its true, 0.9 recurring does equal 1. Its not even up for discussion in the world of maths really, everyone- uni professors, teachers, whatever, everyone accepts it's equal to 1.
The point is that there are several proofs for it and in the world of maths you have to disprove all the proofs. If even one proof cannot be disproved then it is true. Thats all there is to it. People nit pick about infinity and 1/3 not equalling 0.3 recurring, but They Are Wrong!

 

i shall do it my way as most other people have before me...

x=0.999999....
10x=9.999999....

9.999999 (10x)
- 0.999999 (x)
---------------
9.000000 (9x)

9x=9/10 or 90%

 

this is funny shit

 

Remember PEMDAS? well that means you don't subtract 1*.999 from 10*.999 before multiplying. This is especially important because 0.99999 repeating is such a weird value.
Multiply before subtracting and it'll come out right.

.3 repeating does equal 1/3 and .6 repeating does equal 2/3
you're right .9 does not equal 1 but .9 repeating does. Try dividing 1 by three on the calculator on your computer.
Quit being ageist

X never acts as a constant, X is a variable. A variable is a symbol used in place of a constant or other value(s). In this case we know X stands in the place of 0.999 repeating so we can replace the 1X on the left side of the equation in [ 10X - 1X = 9.999- 1X ] with 0.999 repeating using the substitution axiom.
Also it's stupid to have an equation thats proves the given. You might as well say "X=0.999 and that's the truth, so there"

You didn't prove 9x=9/10 at all.
if 9=9x as you suggest in the subtraction you did, then x=1

 

ok if X = 0.999 then 10X = 9.990, not 9.999.
if it is a repeating .9999999999, then yes of course they are equal.