Theorem 6.18 (The tube lemma). Let X × Y be a product space with Y compact. If U is an open set of X × Y containing the set xo × Y, then there is some open set W in X containing x, such that U contains W × Y (called a “tube" around xo × Y).

Theorem 6.18 (The tube lemma). Let X × Y be a product space with Y compact. If U is an open set of X × Y containing the set xo × Y, then there is some open set W in X containing x, such that U contains W × Y (called a “tube" around xo × Y).

Name: Could you explain how to show 6.18 in detail? Theorem 6.18 (The tube l
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Description: Could you explain how to show 6.18 in detail? Theorem 6.18 (The tube lemma). Let X × Y be a product space with Y compact. If Uis an open set of X × Y containing the set xo × Y, then there is some open set W in Xcontaining x, such that U contains W ×

Elements Of Modern Algebra

8th Edition

ISBN:9781285463230

Author:Gilbert, Linda, Jimmie

Publisher:Gilbert, Linda, Jimmie

Chapter3: Groups

Section3.3: Subgroups

Problem 27E: (See Exercise 26) Let A be an infinite set, and let H be the set of all fS(A) such that f(x)=x for...

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