I'm trying to improve myself. I'm the new, better Jerm

Join Date: Jun 2006

Location: Okokomaiko

Posts: 802

Iceman, that is why I keep telling you that .9 repeating isn't a single number but is increasing. Anyway the difference between .9 repeating and 1 is .000...000001 (adjust the zeros to the number of 9's minus 1.

Quote:

Okay einstein...

What is wrong with this equation

x=0.9 repeating

It's wrong because .9 repeating isn't a single number.

STOP ASKING STUPID QUESTIONS BEFORE I HEAT YOU UP.

In order for youre 3rd statement to be true, there would have to be a 0 at the end of the 9.9 repeating once you multiply it by 10. IE If you multiply .9 with 10 9s, by 10 you would get 9.999999999-.9999999999which gives you 8.9999999991=9x. Then when you divide by 9 you would get .9 with 10 9s. That would work no matter how many nines you put on it but the point is that when you multiply by 10 you are moving the decimal point to the left 1 so the .9 r that you are subtracting would have one more 9 to the right of the decimal no matter what number of 9s you decided to use for the begining.

So thats why 0.9 REPEATING is equal to 1 and no other 0.9 with 50 9 behind it....

0.9 repeating is the special number, and the one that works here...Because it is the one that equals 1

Iceman, that is why I keep telling you that .9 repeating isn't a single number but is increasing. Anyway the difference between .9 repeating and 1 is .000...000001 (adjust the zeros to the number of 9's minus 1.

It's wrong because .9 repeating isn't a single number.

STOP ASKING STUPID QUESTIONS BEFORE I HEAT YOU UP.

Okay...Yeah...

0.9 repeating is a line right?

I am sorry...But its called a number...I believe an irrational number...keyword:NUMBER

At the end of your original message, you said 0.9 repeating doesn't work here...

End of story..

Look at it this way

9 + 0.9r - 0.9r = 9

They cancel each other out

The problem is that .9 repeating isnt a real number. No matter what number you carry it out to, once you multiply it by 10 the decimal would move to the right 1 which would leave you with a 0 in the last spot if you subtracted the original number out. You just arent grasping the point, no matter how many 9s you put there, once you multiply it by 10 there is one less 9 to the right of the decimal in that number than there is to the right of the original X so you are subtracting equals. You then end up with 8.9(1 less than however many 9s you started with)1=9x. You then end up with x=however many 9s you started with. Like I said for all intents and purposes it works but truthfully its not. Think about it this way, if you have.9with 100 Octillion 9s behind it no matter what you do when you multiply it by 10 you are gonna have 9.9with 100 octillion 9s-1 which is how you end up with the 8.9 number. The problem is that you cant truthfully multiply an infinite number BECAUSE it changes. If you want to call it infinite than you can never multiply it because you are never done writing it. However if you do multiply it, you end up with 1 less than there would be on the right of the decimal for the original X no matter how you do it.

You asked how it was wrong. That is how its wrong. You arent carrying the .9 repeating out as far in the third step as you did in the original.

The problem is that .9 repeating isnt a real number. No matter what number you carry it out to, once you multiply it by 10 the decimal would move to the right 1 which would leave you with a 0 in the last spot if you subtracted the original number out. You just arent grasping the point, no matter how many 9s you put there, once you multiply it by 10 there is one less 9 to the right of the decimal in that number than there is to the right of the original X so you are subtracting equals. You then end up with 8.9(1 less than however many 9s you started with)1=9x. You then end up with x=however many 9s you started with. Like I said for all intents and purposes it works but truthfully its not. Think about it this way, if you have.9with 100 Octillion 9s behind it no matter what you do when you multiply it by 10 you are gonna have 9.9with 100 octillion 9s-1 which is how you end up with the 8.9 number. The problem is that you cant truthfully multiply an infinite number BECAUSE it changes. If you want to call it infinite than you can never multiply it because you are never done writing it. However if you do multiply it, you end up with 1 less than there would be on the right of the decimal for the original X no matter how you do it.

You asked how it was wrong. That is how its wrong. You arent carrying the .9 repeating out as far in the third step as you did in the original.

Thats the whole point though...That it is infinite...

You can only subtract an infinite amount of 9s from an infinite amount of 9s and nothing else...Giving the value to become a 0...

There isn't going to be one less...It goes on forever...Its called infinity...I see what you are saying, but there isn't one less 9...

Tell me this...What number comes after 0.9 repeating, but is still less than 1? Theere has to be something there if it isn't equal...What is it?

this guy really seems like a bot...i'm repeating myself, but your first premise is false and you can't argue it. 1/3 isn't equal 0.3 repeating, 0.3 repeating is just closest simplification made up so 1/3 could be written at all. you can't write 1/3's decimal value as you think you can, because 0.3 repeating x 3 is not 1, it's just 0.9 repeating and never 1...as for your idiotic point that there must be something between 0.9 repeating and 1, answer is that it doesn't, because there is infinite amount of numbers just between every RATIONAL number, and this one is irrational...we can never know what is between one rational and one irrational number simply because we can't write irrational number as x/y (with x and y integers, that's why it's called so in the first place, we can never know it's true value)...and 0.3 repeating is irrational...and the fact we can't know what is between these two numbers DOESN'T AND CAN'T MAKE THEM EQUAL...for further explanation go find your maths teacher and not spam the forum with this BULL****. you probably think you're very smart and stuff, or that you made a breakthrough discovery, but believe me, you're either very,very stupid or just intentionally making up this stuff just for fun...if it's first, take some math classes, if it's second just go out and get a life

As someone who systematically studied math and especially the concept of LIMIT at an advanced level, I can tell everyone that "0.9 repeating= 1", not approximately, but absolutely. I was even shown a few ways to prove that when I was attending a Olympic Math class 7 years ago.

I am not gonna spend time on rigorously proving it here, I will just say that 0.9 repeating is simply another way to say 1, see the following demostration and you will know why:

8/9? 0.8 repeating 9/9? 0.9 repeating logically and it's equal to 1

Anyway, it is actually not about math itself but about definitions. 0.9 repeating equals 1 is for the same reason 0.3 repeating equals 1/3. There is no argument for that, it's already defined that way.

1/9 isn't exactly 0.1 repeating because 0.1 x 9 is 0.9 repeating and not exactly 1...there "may" be the way to prove it with advanced calculations and limits (i probably wouldn't understand it though) but that's surely not what thread starter meant, he's just repeating same stupid "proofs" over and over again

1/9 isn't exactly 0.1 repeating because 0.1 x 9 is 0.9 repeating and not exactly 1...there "may" be the way to prove it with advanced calculations and limits (i probably wouldn't understand it though) but that's surely not what thread starter meant, he's just repeating same stupid "proofs" over and over again

Seriously my friend, if you don't know that "1/9 = 0.1 repeating" by definition, then I can't help you. think about " 0.9 is just another way to say 1" after you finally got convinced that "1/9=0.1 repeating" after going through all maths text books on this planet.