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It is possible to explain me the 18th proof of the irrationality of square root of 2 from the following site?

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closed as not a real question by Robin Chapman, Scott Morrison Jun 26 '10 at 18:22

It's difficult to tell what is being asked here. This question is ambiguous, vague, incomplete, overly broad, or rhetorical and cannot be reasonably answered in its current form. For help clarifying this question so that it can be reopened, visit the help center.If this question can be reworded to fit the rules in the help center, please edit the question.

The proof looks perfectly clear to me, except for a typo; CG=CD should be CG=GD (which is correctly stated earlier). What needs explanation? (This doesn't seem appropriate for MathOverflow.) – Andreas Blass Jun 26 '10 at 17:31
Closed, please check the FAQ. – Scott Morrison Jun 26 '10 at 18:24
Christian: on a side note, you may like the analogous elementary proof of the irrationality of the other classic number, the golden ratio. Since it verifies the relation x=1+1/x and 1<x<2, if x were rational, x=p/q with 0<q<p, then also x=q/(p-q), and 0<p-q<q so there is no minimal denominator, a contradiction. – Pietro Majer Jun 26 '10 at 18:33
-1 for not saying what the questioner doesn't understand... – Yemon Choi Jun 26 '10 at 19:37
In the future, you'd have better luck directing such questions to sites like – Qiaochu Yuan Jun 26 '10 at 22:09

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