Decimals Question

[Catseye]

I've got headache now and need to dive under the duvets in the pitch dark-can we just stick to simple VR and English.

Please.

[russet]

I was merely pointing out to catseyes, I had not posted.

I would rather just leave it at that.

[Catseye]

How can such an innocent thread become so contentious ?

The Catseye effect ??

That's mathematician/scientist for you

Best to be an idiot like myself.

[Surferfish]

Pleased to see my little question has provoked such debate!

Guest55 already provided one proof. Here's another (probably the same thing written in a slightly different way):

1/9 = 0.111...

Agreed? Check on a calculator if you want to be sure. Then multiplying each side by 9 gives:

9 x 1/9 = 9 x 0.111...

Therefore,

1 = 0.999....

QED

[Catseye]

Pleased to see my little question has provoked such debate!

Guest55 already provided one proof. Here's another (probably the same thing written in a slightly different way):

1/9 = 0.111...

Agreed? Check on a calculator if you want to be sure. Then multiplying each side by 9 gives:

9 x 1/9 = 9 x 0.111...

Therefore,

1 = 0.999....

QED

I don't care, I'm still under covers and refuse to come out until we all makeup and kiss.

[Catseye]

1=2

Assume that we have two variables a and b, and that: a = b

Multiply both sides by a to get: a2 = ab

Subtract b2 from both sides to get: a2 - b2 = ab - b2

This is the tricky part: Factor the left side and right side

> (a + b)(a - b) = b(a - b)

Since (a - b) appears on both sides, we can cancel it to get: a + b = b

Since a = b (that's the assumption we started with), we can substitute b in for a to get: b + b = b

Combining the two terms on the left gives us: 2b = b

Since b appears on both sides, we can divide through by b to get: 2 = 1 !!

Apart from g55 can anyone else spot why this as a mathematical fallacy ?

I crawl back under my duvet now.

[Catseye]

Come up to meet you, tell you I'm sorry
You don't know how lovely you are

I had to find you
Tell you I need you
Tell you I set you apart

Tell me your secrets
And ask me your questions
Oh, let's go back to the start

Running in circles
Coming up tails
Heads on a science apart

Nobody said it was easy
It's such a shame for us to part
Nobody said it was easy
No one ever said it would be this hard

Oh, take me back to the start

I was just guessing
At numbers and figures
Pulling the puzzles apart

Questions of science
Science and progress
Do not speak as loud as my heart

Tell me you love me
Come back and haunt me
Oh, and I rush to the start

Running in circles
Chasing our tails
Coming back as we are

Nobody said it was easy
Oh, it's such a shame for us to part
Nobody said it was easy
No one ever said it would be so hard

I'm going back to the start

Questions of science
Science and progress
Do not speak as loud as my heart

Tell me you love me...............Coldplay-The Scientist.

[Surferfish]

(My age) x 0 = 21 x 0

Since zero appears on both sides, we can cancel it to get:

My age = 21

[Catseye]

(My age) x 0 = 21 x 0

Since zero appears on both sides, we can cancel it to get:

My age = 21

Not so fast to cancel we must divide both sides by 0.

X/0=INFINITY
Therefore infinity = infinity ( but some infinities are > than others !!!!-but thats another topic covered in set theory)

Look at the assumptions, "two variables" where a=b.

There is nothing wrong in the arithmetic or algebra.

[Surferfish]

Not so fast to cancel we must divide both sides by 0.

X/0=INFINITY
Therefore infinity = infinity ( but some infinities are > than others !!!!-but thats another topic covered in set theory)

Look at the assumptions, "two variables" where a=b.

There is nothing wrong in the arithmetic or algebra.

That seems a bit unfair. How come you're allowed to divide by zero and not me?!

Since (a - b) appears on both sides, we can cancel it