
What is infinity divided by infinity? - Mathematics Stack Exchange
Aug 11, 2012 · I know that $\\infty/\\infty$ is not generally defined. However, if we have 2 equal infinities divided by each other, would it be 1? if we have an infinity divided by another half-as …
Finding a basis of an infinite-dimensional vector space?
For many infinite-dimensional vector spaces of interest we don't care about describing a basis anyway; they often come with a topology and we can therefore get a lot out of studying dense …
How can I define $e^x$ as the value of infinite series?
Are you familiar with Taylor series? Series solutions of differential equations at regular points? From what foundation/background are you approaching this problem?
linear algebra - What can be said about the dual space of an …
The dual space of an infinite-dimensional vector space is always strictly larger than the original space, so no to both questions. This was discussed on MO but I can't find the thread.
real analysis - Meaning of Infinite Union/Intersection of sets ...
Meaning of Infinite Union/Intersection of sets Ask Question Asked 8 years, 8 months ago Modified 4 years, 1 month ago
general topology - Why is the infinite sphere contractible ...
Why is the infinite sphere contractible? I know a proof from Hatcher p. 88, but I don't understand how this is possible. I really understand the statement and the proof, but in my imagination this...
real analysis - Examples of sets that have infinite measure ...
Nov 17, 2021 · $\begingroup$"I assume that only uncountably infinite unbounded sets have infinite measure" - This is true in the Lebesgue measure on $\Bbb R$. Any countable set, …
If $S$ is an infinite $\sigma$ algebra on $X$ then $S$ is not …
6 Show that if a $\sigma$-algebra is infinite, that it contains a countably infinite collection of disjoint subsets. An immediate consequence is that the $\sigma$-algebra is uncountable.
Does infinite equal infinite? - Mathematics Stack Exchange
All three integrals are divergent and infinite and have the regularized value zero, but two of them are equal but not equal to the third one. In other cases of divergent integrals or series, the …
Infinite class of closed sets whose union is not closed
Aug 4, 2016 · 0 Since singletons in R are closed in usual topology. We can think about infinite class of singletons {x} where x belongs to (0,1] then there union will be (0,1] which is not …