Path: ...!eternal-september.org!feeder3.eternal-september.org!news.eternal-september.org!.POSTED!not-for-mail From: "Chris M. Thomasson" Newsgroups: sci.logic,sci.math Subject: Re: Replacement of Cardinality Date: Thu, 15 Aug 2024 23:48:27 -0700 Organization: A noiseless patient Spider Lines: 19 Message-ID: References: <75e2ce0e-7df8-4266-968b-9c58e4140b03@att.net> <35d8c0a1-dab3-4c15-8f24-068e8200cb07@att.net> <4412ba58-855f-401d-9fd0-879d5cb50062@att.net> <219eed30-9918-4759-9b7e-826088fc91c9@att.net> <0aae40c7-1092-4b12-99dc-290aa5a94021@att.net> <80662980-e93e-4af4-9489-f17fad3097d1@att.net> MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8; format=flowed Content-Transfer-Encoding: 8bit Injection-Date: Fri, 16 Aug 2024 08:48:29 +0200 (CEST) Injection-Info: dont-email.me; posting-host="8b28403f99ffa92bcc2694c54178d92d"; logging-data="1429171"; mail-complaints-to="abuse@eternal-september.org"; posting-account="U2FsdGVkX1+0EQmAq4Ul2CYnH8vOhEWLxZRQgUXJlxE=" User-Agent: Mozilla Thunderbird Cancel-Lock: sha1:BE0HNUcA88gCeIbT11hEH8VwjRI= Content-Language: en-US In-Reply-To: Bytes: 2313 On 8/15/2024 10:57 PM, Moebius wrote: > Am 16.08.2024 um 07:50 schrieb Moebius: > >> Of course, _if_ we already have introduced the real numbers (i.e. IR) >> we may define >> >>        √2 = the real number x such that x^2 = 2 ,    (*) >> >> _after_ we have shown that that there is exactly one x e IR such that >> x^2 = 2. >> >> From (*) we get immediately: (√2)^2 = 2 > > Now we may assume that there are natural numbers n,m such that √2 = n/m. > > (...) The infinite convergents of continuous fractions can describe sqrt(2) up to any desired precision?