Solve Math Puzzle: 0.999... ≠ 1

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In summary, 0.999... and 1 may appear to be different numbers, but they are actually two different ways of representing the same value. This is because 0.999... is an infinite decimal while 1 is a whole number. There are multiple ways to prove that they are equal, including using the concept of limits in calculus. The concept of infinity is crucial in understanding this equality, as 0.999... has no endpoint and can never surpass 1. This knowledge can be useful in solving math puzzles involving infinite decimals, fractions, and the concept of infinity in mathematics.
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Fala483
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Let f(n) be of the form F(1) = 0.999999 F(2) = 0.9999999 F(3) = 0.99999999 Etc

For arbitrary N >= 1

Let g(n) = f(n)^2

G(1) and g(2) end in 8

By linear relation all g(n) end in 8

Assume 0.999... = 1

0.999... X 0.999... must end in 8 per (4)

1 x 1 does not end in 8

By (5),(6),(7), contradiction

Therefore 0.999... = 1 is a contradiction
 
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Fala483 said:
Let f(n) be of the form F(1) = 0.999999 F(2) = 0.9999999 F(3) = 0.99999999 Etc

For arbitrary N >= 1

Let g(n) = f(n)^2

G(1) and g(2) end in 8
No. How are you getting 8 as the final digit?
Let's start in a more organized fashion.
##f_1 = 0.9##
##f_2 = 0.99##
##f_3 = 0.999##
Then ##f_1^2 = 0.81##
##f_2^2 = 0.9801##
##f_3^2 = 0.99801##
and so on. The sequence ##\{f_1, f_2, f_3, \dots \}## is approaching 1, which is easy to prove,
and it can easily be shown that the sequence ##\{f_1^2, 4_2^2, f_3^3, \dots \}## also has 1 as its limit.
Fala483 said:
By linear relation all g(n) end in 8
No
Fala483 said:
Assume 0.999... = 1

0.999... X 0.999... must end in 8 per (4)

1 x 1 does not end in 8

By (5),(6),(7), contradiction

Therefore 0.999... = 1 is a contradiction
No.
Thread closed.
 
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1. How can 0.999... be different from 1 if they represent the same number?

Although 0.999... and 1 may appear to be different numbers, they are actually two different ways of representing the same number. This is because 0.999... is an infinite decimal that continues forever, while 1 is a whole number with no decimal places. Therefore, even though they may look different, they are equivalent and represent the same value.

2. Can you prove that 0.999... is equal to 1?

Yes, there are multiple ways to prove that 0.999... and 1 are equal. One way is to use the concept of limits in calculus, which shows that as the number of 9s in 0.999... increases, the difference between 0.999... and 1 approaches 0. Therefore, 0.999... is infinitely close to 1 and can be considered equal to it.

3. How does the concept of infinity play a role in understanding 0.999... ≠ 1?

The concept of infinity is crucial in understanding why 0.999... and 1 are equal. Since 0.999... is an infinite decimal, it continues on forever without an endpoint. Therefore, there is no way for 0.999... to be anything other than equal to 1, as it would require an infinite number of 9s to make the two values different.

4. Is it possible for 0.999... to be greater than 1?

No, it is not possible for 0.999... to be greater than 1. As mentioned before, 0.999... is infinitely close to 1, and there is no way for it to surpass 1. This is because the concept of infinity means that there is no endpoint to the decimal expansion of 0.999..., so it will never be greater than 1.

5. How can I use this knowledge of 0.999... ≠ 1 in solving math puzzles?

Understanding that 0.999... and 1 are equal can be useful in solving math puzzles that involve infinite decimals or limits. It can also help in understanding and solving problems involving fractions and decimals, as well as in understanding the concept of infinity in mathematics.

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