Linear combinations of partitions of unity with restricted supports
نویسندگان
چکیده
منابع مشابه
Linear combinations of partitions of unity with restrictedsupportsChristian
Given a locally nite open covering fC : 2 Ig of a T 4-space X we characterize all real-valued functions f 2 C(X) which admit a representation f = P 2I ' with 2 IR and a partition of unity f' : 2 Ig fulllling the restriction supp(') C. The crucial lemma concerns a particular way of extending partitions of unity in the sense of the Tietze-Urysohn theorem. As an application, we determine the class...
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ژورنال
عنوان ژورنال: Studia Mathematica
سال: 2002
ISSN: 0039-3223,1730-6337
DOI: 10.4064/sm153-1-1