Rudin's Equations 3 & 4 Explained

[fmegally]

Hello everybody. I started readin baby rudin a few days ago. And i came across equations 3 and 4 on page 2 of chapter 1. They seem a bit mysterious to me, does anybody know where did they come from?

Thanks in advance for your help
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[aleury]

I asked my professor that same question. They pretty much said that someone really clever (maybe Rudin? I don't know) came up with it.

 

[HallsofIvy]

First, Rudin wrote many texts, notably the analysis texts called, simply "Rudin" and "baby Rudin" but others as well. We don't know which texts you are talking about. Second, even if you told us what text you mean, many of us do not have available to consult. Perhaps if you posted the equations in question?