Abstract
If X is a set, then x ∈ X means that x is an element of X, while y ∉ X means that y is not an element of X. A set which has a single element x is denoted by (x). On logical grounds, it is necessary to distinguish between an object x and the set (x) consisting of the single object x. However, as a matter of notational convenience we shall use frequently the same symbol for an object x and the set consisting of the single object x. It is also convenient to use the concept of the empty set which has no element. The empty set will be denoted by the symbol Ø.
This is a preview of subscription content, log in via an institution to check access.
Access this chapter
Tax calculation will be finalised at checkout
Purchases are for personal use only
Preview
Unable to display preview. Download preview PDF.
Author information
Authors and Affiliations
Rights and permissions
Copyright information
© 1955 Springer-Verlag OHG. in Berlin, Göttingen and Heidelberg
About this chapter
Cite this chapter
Rado, T., Reichelderfer, P.V. (1955). Background in topology. In: Continuous Transformations in Analysis. Die Grundlehren der Mathematischen Wissenschaften, vol 75. Springer, Berlin, Heidelberg. https://doi.org/10.1007/978-3-642-85989-2_1
Download citation
DOI: https://doi.org/10.1007/978-3-642-85989-2_1
Publisher Name: Springer, Berlin, Heidelberg
Print ISBN: 978-3-642-85991-5
Online ISBN: 978-3-642-85989-2
eBook Packages: Springer Book Archive