On inversely $\theta$-semi-open and inversely $\theta$-semi-closed functions

  • J. Sanabria Universidad de Sucre, Facultad de Educación y Ciencias, Departamento de Matemáticas, Carrera 28 No. 5-267 Barrio Puerta Roja, Sincelejo, Colombia
  • E. Rosas Universidad de la Costa, Departamento de Ciencias Naturales y Exactas, Barranquilla, Colombia & Departamento en Matemáticas, Universidad de Oriente, Cumaná, Venezuela
  • L. Vásquez Instituto Superior de Formación Docente Salomé Ureña-ISFODOSU, Recinto Emilio Prud’Homme, Calle R.C. Tolentino # 51, esquina 16 de Agosto, Los Pepines, Santiago de los Caballeros, República Dominicana
Keywords: Inversely semi-open function, θ-open set, θ-closed set, inversely θ- semi-open function, inversely θ-semi-open function, strongly θ-continuous function.


In this paper, we introduce the concepts of inversely $\theta$-semi-open and inversely $\theta$-semi-closed functions and obtain their characterizations if it is possible in terms of $\theta$-closure and $\theta$-interior by using sets determined by the fibres of the function. Finally, we obtain its relationships with the strongly $\theta$-continuous.


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How to Cite
Sanabria J, Rosas E, VásquezL. On inversely $\theta$-semi-open and inversely $\theta$-semi-closed functions. Mat. Stud. [Internet]. 2020Mar.17 [cited 2020Apr.5];53(1):92-9. Available from: http://matstud.org.ua/ojs/index.php/matstud/article/view/26