Need help on some problems w/ accumulation points

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In summary, accumulation points, also known as limit points or cluster points, are points in a sequence or set that are infinitely close together. They are often used to describe the behavior of a sequence or set as it approaches a limit. To determine if a point is an accumulation point, you can use the definition which states that a point is an accumulation point if every neighborhood of that point contains infinitely many points of the sequence or set. There is a subtle difference between accumulation points and limit points, as accumulation points refer to points in a sequence or set that are infinitely close together, while limit points are the points that the sequence or set approaches as it approaches a limit. Accumulation points have various applications in mathematics, physics, and engineering, and
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philbein
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Homework Statement


Give an example of a set with exactly two accumulation points.



Homework Equations


We can use the defintion of accumulation points

The Attempt at a Solution



I really have no idea where to get started on this. If I could get a hint that would be great thank you
 
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Well, you listed the "definition of accumulation points" as a "relevant equation"! What is that definition.

Suppose you had a sequence such as {1, 1/2, 1/3, ..., 1/n, ...}. That is a set of real numbers. What are its accumulation points?
 

1. What are accumulation points?

Accumulation points, also known as limit points or cluster points, are points in a sequence or set that are infinitely close together. They are often used to describe the behavior of a sequence or set as it approaches a limit.

2. How do I determine if a point is an accumulation point?

To determine if a point is an accumulation point, you can use the definition which states that a point is an accumulation point if every neighborhood of that point contains infinitely many points of the sequence or set. You can also check if the point is a limit point by seeing if it is the limit of a subsequence.

3. What is the difference between an accumulation point and a limit point?

While the terms are often used interchangeably, there is a subtle difference between accumulation points and limit points. Accumulation points refer to points in a sequence or set that are infinitely close together, while limit points are the points that the sequence or set approaches as it approaches a limit.

4. How are accumulation points used in real-world applications?

Accumulation points have various applications in mathematics, physics, and engineering. They are used to describe the behavior of a system or sequence as it approaches a limit, and they can also help in finding the limit of a function or sequence.

5. Are accumulation points the same as accumulation functions?

No, accumulation points and accumulation functions are not the same. As mentioned earlier, accumulation points refer to points in a sequence or set, while accumulation functions refer to mathematical functions that describe the accumulation of a quantity over time.

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