Possible Typo in Topology... > Classification... about complex-analysis.github.io

[wdnaeng]

Also, a request for clarification on the third example. If $S_3$ is the closed deleted neighborhood, how is it that its interior contains $z_0$ (is equal to the open neighborhood)?

Should it maybe read $\text{Int } S_3=B_{\frac{1}{2}}\left(2+\sqrt{3}i\right)\setminus \lbrace2+\sqrt{3}i\rbrace$ ?

My understanding of the previous section is that $\text{Int}$, $\text{Ext}$, and $\partial$ have no overlap, but you write that $$\partial S_3=\lbrace z:|z-\left(2+\sqrt{3}i\right)|=\frac{1}{2}\rbrace \cup \lbrace2+\sqrt{3}i\rbrace$$ which contains $z_0$.

Am I misunderstanding something fundamental?

[jcponce]

Hi!

Thanks for reporting the typos. The imaginary constant is missing. For the second issue, yes you are right about the interior of S_3. I will fix it.

I am you are enjoying the content of this site.

Kind regards.

[jcponce]

All fixed now! :) By the way, the site will be down from the 25th until 31 March 2024. I will make a major update. Check the details in my Patreon:

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