Every sequence of real bounded functions has convergent sub?

In summary, the conversation suggests that the individual has found a solution to a problem and is wondering how to remove the question from the forum. However, it is suggested that leaving the question and providing an answer or outline of the answer would be more beneficial to other members of the forum.
  • #1
RBG
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I figured it out... how do I remove this question?
 
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  • #2
I don't know the answer, but I have an answer in the case ##x## belongs to finite set of rationals ##S = \{ x_1,...,x_p\} \subset \mathbb{Q}##. It may or may not be useful for what you want to prove.

  1. ## \{f_n(x_1) \}## is a real bounded sequence so there is a converging subsequence ## \{f_{\sigma_1(n)}(x_1) \}## that converges to ##f(x_1)##
  2. ## \{f_{\sigma_1(n)}(x_2) \}## is a real bounded sequence so there is a converging subsequence ## \{f_{(\sigma_2 \circ \sigma_1)(n)}(x_2) \}## that converges to ##f(x_2)##. Furthermore ## \{f_{(\sigma_2 \circ \sigma_1)(n)}(x_1) \}## converges to ##f(x_1)## as a subsequence of ## \{f_{\sigma_1(n)}(x_1) \}##.
  3. Repeating this process, you have ##\{ f_{(\sigma_p\circ ... \circ \sigma_1)(n)}(x_i)\} ## convergerges to ##f(x_i)## for all ##i = 1... p##.
 
  • #3
RBG said:
I figured it out... how do I remove this question?
Why remove the question?

Wouldn't it be more helpful to other members of the forum to leave the question, and post the answer (or at least an outline of the answer)?
 
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1. What is the meaning of "Every sequence of real bounded functions has convergent sub"?

The statement means that for any sequence of real bounded functions, there exists a subsequence that converges to a limit. In other words, no matter how the sequence is constructed, there will always be a subsequence that approaches a specific value.

2. Why is this statement important in mathematics?

This statement is important because it allows us to prove the existence of a limit for a sequence of real bounded functions. It also helps us understand the behavior of a sequence, as we can focus on the convergent subsequence rather than the entire sequence.

3. What is the proof for this statement?

The proof for this statement involves using the Bolzano-Weierstrass theorem, which states that every bounded sequence has a convergent subsequence. By applying this theorem to each individual function in the sequence of real bounded functions, we can prove that the overall sequence also has a convergent subsequence.

4. Can this statement be applied to other types of functions?

Yes, this statement can be applied to other types of functions as long as they are bounded and defined over the real numbers. It can also be extended to sequences of functions in higher dimensions, such as sequences of vector-valued functions.

5. Are there any exceptions to this statement?

No, this statement holds true for all sequences of real bounded functions. However, it is important to note that the limit of the convergent subsequence may not necessarily be the same as the limit of the original sequence. Additionally, the limit of the overall sequence may not exist even though there are convergent subsequences.

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