- #1

Mr Davis 97

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## Homework Statement

Show that it is not necessarily true that the infinite union of closed sets is closed

## Homework Equations

## The Attempt at a Solution

From intuition, I came up with the following counter-example: ##\displaystyle \bigcup_{n=2}^{\infty} \left[ \frac{1}{n}, \frac{n}{n+1} \right] = (0,1)##. However, I am not sure how to actually

*prove*that this infintie union is the set on the right. How would I do so?