Cantor's Proof of (0,1]~[0,1] Bijection Explained

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SUMMARY

Cantor's proof of the existence of a bijection between the intervals (0,1] and [0,1] is established through a specific mapping technique. The mapping involves transforming the endpoints of the interval [0,1] to (0,1] by defining a sequence where each point in [0,1] is mapped to a corresponding point in (0,1]. For example, 0 is mapped to 1/2, 1/2 to 1/3, and so forth, while all other points remain unchanged. This creates a one-to-one correspondence, demonstrating that the two sets have the same cardinality.

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catherinenanc
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1. Can anybody elxplain to me (or point me to a URL of an explanation) how Cantor proved the existence of a bijection (0,1]~[0,1]?
2. It's not for homework. I have to understand it generally for a paper I am writing.
3. I think it has something to do with transfinites but I can't get it.
 
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I don't know if it is how Cantor did it but it is easy enough. To map [0,1] to (0,1] try this:
##0\rightarrow \frac 1 2##
##\frac 1 2 \rightarrow \frac 1 3##
##\frac 1 3 \rightarrow \frac 1 4##
##\frac 1 4 \rightarrow \frac 1 5##
...
##\frac 1 n \rightarrow \frac 1 {n+1}##
Map all other points into themselves. That gives a 1-1 correspondence between the two intervals.
 

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