Hi guys. I'm apprently stuck on the basics of the analysis. On the proof that Q lacks least upper boundary property to be precise.(adsbygoogle = window.adsbygoogle || []).push({});

The example I have uses a set A (p in Q | p > 0, p^2 < 2)

then q is defined as [tex]p - \frac{p^{2} - 2}{p + 2}[/tex] . Then they show that if p is in A then q is in A too and p < q and so on. All very simple.

What I can't understand is where the expression for q comes from - logically: why p^{2}- 2 and over p + 2. I see it works, but I need to know why :)

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# Q and least-upper boundary.

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