tmp goto [[경계,bound]]

greatest '''lower bound''' = 최대'''하계''' = 하한 = infimum → [[하한,infimum]]

'''하계'''(lower bound)가 존재하면 그 집합은 "bounded from below"라고 한다.
https://mathworld.wolfram.com/BoundedfromBelow.html
cf. from을 뺀
https://proofwiki.org/wiki/Definition:Bounded_Below

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Compare: [[상계,upper_bound]]

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[[https://terms.naver.com/entry.naver?docId=3405404&cid=47324&categoryId=47324 수학백과: 하계]]
https://mathworld.wolfram.com/LowerBound.html
https://everything2.com/title/lower+bound

https://proofwiki.org/wiki/Definition:Lower_Bound