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torquerotates
Feb6-11, 01:13 PM
Does the Archimedean property work for unbounded sets? My book does a proof of the Archimedean property relying on the existence of sup which relies on the existence of a bound.

eabod
Feb6-11, 04:58 PM
Does the Archimedean property work for unbounded sets? My book does a proof of the Archimedean property relying on the existence of sup which relies on the existence of a bound.

Unbounded sets of what type of elements? Real numbers? I think you should reword or provide more details of your question and maybe even cite the text you're referring to (including page number, theorem number, etc.).

Preno
Feb6-11, 06:28 PM
The real numbers are unbounded and have the Archimedean property.

spamiam
Feb7-11, 03:14 PM
If I'm recalling the proof of the Archimedean property correctly, I wonder if the OP actually meant to ask if this property holds true for sets that do not satisfy the Axiom of Completeness (i.e., the existence of sups)...

I suppose the rational numbers are an example of a set that satisfies the Archimedean property without satisfying the Axiom of Completeness.