Jump to content
BrainDen.com - Brain Teasers
  • 0


Guest
 Share

Question

Recommended Posts

  • 0

Actually, 1 = 0.999... is true.

Also, 0.999... + 0.999... = 1.999... = 2

How can 1 = 0.999... be true , considering no matter how you finish it

(and I realize you're not)

there must be a value e

where .999.... + e = 1

math was a long time ago...

steve

Link to comment
Share on other sites

  • 0

How can 1 = 0.999... be true , considering no matter how you finish it

(and I realize you're not)

there must be a value e

where .999.... + e = 1

math was a long time ago...

steve

He is talking about an infinite number of 9's.

If there are an infinite number of 9's then

it is true that 0.999.... = 1

Here is why:

Let's first not do an infinite number of 9's but rather n of them. Let X(n) be this number, so

X(1) = .9

X(2) = 0.99

X(3) = 0.999

X(4) = 0.9999

You get the idea.

It is not hard to verify that X(n) has the expression:

X(n) = 1-10^(-n)

Taking the limit of this expression as n goes to infinity makes 10^(-n) go to zero.

Lim as n-> infinity X(n) = 1 - 0 = 1

You might find it unbelievable to think about an infinite number of 9's in 0.9999...

but think about this:

why don't you find it unbelievable to think about an infinite number of 0's in 1.0000.....

Whenever you talk about the number 1 you are actually talking about a 1 with an infinite number of 0's in the decimal place.

It is just as much of a stretch --- infinite digits I mean.

Your argument could be turned to say no matter how many 0's you have, there will exist an e such that

1.0000... - e = 1

One would never argue this, but it is as valid of an argument as the infinite number of 9's.

Perhaps that will convince you to believe that 0.999... is actually 1.

Link to comment
Share on other sites

  • 0

How can 1 = 0.999... be true , considering no matter how you finish it

(and I realize you're not)

there must be a value e

where .999.... + e = 1

math was a long time ago...

steve

What is the value of e in .999...+e=1?

Is it e=.000...1? If so, isn't that just 0 meaning .999...=1?

If not, and you think that e>0, then please tell me how to write the number that is equal to 1-e/2. If e is greater than 0 then you must agree that 1>(1-e/2)>.999... So how does one write 1-e/2?

If you can't figure it out, the reason why is because e is actually 0 in this case. .999...=1.

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Answer this question...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

Loading...
 Share

  • Recently Browsing   0 members

    • No registered users viewing this page.
×
×
  • Create New...