(Un-)Countable union of open sets - Mathematics Stack Exchange
Jun 4, 2012 · A remark: regardless of whether it is true that an infinite union or intersection of open sets is open, when you have a property that holds for every finite collection of sets (in …
Newest Questions - Mathematics Stack Exchange
2 days ago · Mathematics Stack Exchange is a platform for asking and answering questions on mathematics at all levels.
Como calcular el area de la superficie de un huevo con calculo
Estoy haciendo mi reciente evaluación interna del IB Matemáticas HL y mi tema es cómo calcular el área de superficie de un huevo . Quiero aplicar el cálculo conocimiento en esta pregunta, …
If a series converges, then the sequence of terms converges to $0$.
@NeilsonsMilk, ah, it did not even occur to me that this involves a step. See, where I learned mathematics, it is not unusual to first define when a sequence converges to zero (and we have …
Double induction example: $ 1 + q + q^2 + q^3 + \cdots + q^ {n …
Slightly relevant: you can see my answer on this thread for a proof that uses double induction (just to get you exposed to how the mechanics of a proof using double induction might work).
The sequence of integers $1, 11, 111, 1111, \ldots$ have two …
May 9, 2016 · Prove that the sequence $\ {1, 11, 111, 1111, .\ldots\}$ will contain two numbers whose difference is a multiple of $2017$. I have been computing some of the immediate …
modular arithmetic - Prove that that $U (n)$ is an abelian group ...
Prove that that $U(n)$, which is the set of all numbers relatively prime to $n$ that are greater than or equal to one or less than or equal to $n-1$ is an Abelian ...
Mnemonic for Integration by Parts formula? - Mathematics Stack …
Nov 11, 2018 · The Integration by Parts formula may be stated as: $$\\int uv' = uv - \\int u'v.$$ I wonder if anyone has a clever mnemonic for the above formula. What I often do is to derive it …
probability - Suppose that $U1, U2, ..., Un$ are iid $U (0,1)$ and …
Nov 2, 2022 · I meant it to read: P (S_1 ≤ t) P (S_n ≤t). The product of those probabilities given the assumption is true.
probability - If $U\sim U (-1,1)$ and $N\sim N (0,1)$ are …
Apr 15, 2023 · If $U$ and $N$ are independent r.v.'s (with finite moments of order $4$) then $U$ and $UN$ CANNOT be independent unless $U$ is a constant.