(adsbygoogle = window.adsbygoogle || []).push({}); 1. The problem statement, all variables and given/known data

1. If A and B are closed. Show that A x B is a closed subset of X x Y with the product topology.

2. Give an example of a closed subset W of RxR such that the first component of W (it is made up of two components) is not closed in R.

For 2. How does one recognise a closed subset W in RxR?

For 1. How do you show A x B is closed in general? Is the only way from functions like pi and when one end is open or closed the other must be as well.

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# Homework Help: Closed subsets

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