• 제목/요약/키워드: Continuous function

검색결과 1,798건 처리시간 0.031초

A CONTINUOUS ONE-TO-ONE FUNCTION WHOSE INVERSE IS NOWHERE CONTINUOUS

  • Kim, Won-Kyu;Hong, Sun-Pyo
    • 한국수학교육학회지시리즈B:순수및응용수학
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    • 제18권2호
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    • pp.157-160
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    • 2011
  • Main purpose of this note is to construct an example of a continuous one-to-one function f : ${\mathbb{Q}}^*{\rightarrow}{\mathbb{R}}$ whose inverse is nowhere continuous, and to show that the completeness is not necessary for the continuous inverse theorem.

ON WEAKENED FORMS OF (θ, s)-CONTINUITY

  • Kim, Seungwook
    • Korean Journal of Mathematics
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    • 제14권2호
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    • pp.249-258
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    • 2006
  • The weakened forms of the (${\theta},s$)-continuous function are introduced and their basic properties are investigated in concern with the other weakened continuous function. The open property of a function and the extremal disconnectedness of the spaces are crucial tools for the survey of these functions.

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Fuzzy r-minimal Continuous Functions Between Fuzzy Minimal Spaces and Fuzzy Topological Spaces

  • Min, Won-Keun
    • International Journal of Fuzzy Logic and Intelligent Systems
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    • 제10권2호
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    • pp.124-127
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    • 2010
  • In this paper, we introduce the concepts of fuzzy r-minimal continuous function and fuzzy r-minimal open function between a fuzzy r-minimal space and a fuzzy topological space. We also investigate characterizations and properties for such functions.

ON THE DERIVATIVES OF THE VECTOR-VALUED CONTINUOUS FUNCTION

  • Lee, Choon-HO
    • Journal of applied mathematics & informatics
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    • 제23권1_2호
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    • pp.489-496
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    • 2007
  • Let g be a continuous function on an interval I which is not constant on any subinterval of I, and let ${\mu}$ be a Borel measure on I. In this paper we give a necessary and sufficient conditions guaranteeing, for the strongly measurable function f on I with values in a Banach space X, the existence of a continuous primitive function F on I with respect to g.

함수의 연속을 판단하는 문제에서 현직교사와 예비교사의 정의역 인식 조사 (A study of the in-service teachers' and pre-service teachers' recognition the domain in the problem of the continuity of a function)

  • 이세형;장현석;이동원
    • 한국수학교육학회지시리즈A:수학교육
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    • 제57권4호
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    • pp.477-491
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    • 2018
  • In this paper we study in-service teachers' and pre-service teachers' recognition the domain in the problem concerning the continuity of a function. By a questionnaire survey we find out that most of in-service teachers and pre-service teachers are understanding the continuity of a function as explained in high school mathematics textbook, in which the continuity was defined by and focused on comparing the limit with the value of the function. We also notice that this kind of definition for the continuity of a function makes them trouble to figure out whether a function is continuous at an isolated point, and to determine that a given function is continuous on a region by not considering its domain explicitly. Based on these results we made several suggestions to improve for in-service teachers and pre-service teachers to understand the continuity of a function more exactly, including an introduction of a more formal words usage such as 'continuous on a region' in high school classroom.