I am reading through this proof, but I am stumped as to what the superscript on the left-hand side of the equation means? $q-^2 2$ It looks something like that.
It's the third edition and it was printed in 1976.
Rudin's Analysis Page 2 formula (4), what is the superscript before the 2 mean?
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real-analysis
1 Answers
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My edition is of 1964, and the formulas on page 2 are not numbered. In any case: This is the first time that you see a proof of this kind. Even if there should be a typo at the indicated place, you should be clearly aware of what Rudin wants to prove there, so that you can fill in the exact small print. Don't go to page 3 until you have understood this point.
Rudin put a lot of thought into this proof: In order to show that a $p\in{\mathbb Q}$ with $p^2<2$ cannot be the maximal such $x\in{\mathbb Q}$, by "reverse engineering" he came up with a $q=p+h$, $h>0$, such that $q^2<2$ as well.