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Proof of Limit of a Sequence Raised to a Positive Integer Power

Problem statement:If $\{a_n\}$ is a sequence of positive numbers such that $\lim\limits_{n \to \infty}a_n =L$, prove using $\epsilon, N$ definition\begin{align*}\lim\limits_{n \to \infty}a_n^p =...

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Prove that $\lim _{t \rightarrow \infty}\|f\|=0$

I am reading Paper but I have a difficult in understand the following statementThey proved that $\frac{1}{2} \frac{d}{d t}\|f\|^2=\frac{1}{2} f^{\prime}\left[G+G^{\prime}\right] f+\Sigma \bar{u}_j...

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Sequence with infinite number of zeros

My question reads:Let’s call a sequence $(x_n)$ zero-heavy if there exists $M\in\mathbb{N}$ such that for all $N\in\mathbb{N}$ there exists $n$ satisfying $N\leq\ n\leq\ N + M$ where $x_n = 0$.If a...

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Set f a lower semicontinuous real function. If the set of points such that...

Set $f$ lower semicontinuous real function.Supose the set of x such that $f(x)=c$ is dense.Then $f(x)<= c$ for all $x$ or $f(x) >= c$ for all $x$ ?Im inclined to belive that its the second...

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Show that $\partial ^\beta f(x)=\sum _{\alpha\in\mathbb{N}^n}c_{\alpha +\beta...

Firstly consider the multi-index notation.Let $\{c_\alpha\}_{\alpha\in\mathbb{N}^n}\subseteq\mathbb{R}$ and $x_0:=(x_{01},\cdots,x_{0n})\in\mathbb{R}$.Define $\rho :=\sup\big\{r\in [0,\infty...

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Point of achieving minimum value of a function

In side the triangle lies with corner $(0,1),(0,1/2),(1/2,1/2)$ (lies in the XY Place) where does the function $$f(x,y)=\frac{15554x+5092y+12441}{35360x+11576y+28283}$$ achieves it's minimum value?

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Proof of Great Picard Theorem

I need help please! So I'm reading 'Complex made simple' by David C. Ullrich. I made all the requirements for this proof but the author don't give the proof of this final theorem, instead it gives a...

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Sufficient conditions for uniform convergence in probability

I have a sequence of continuous random variables $\{X_n\}$, with density $f_n(x \mid \theta)$ w.r.t. the Lebesgue measure. $X_n = o_{p_\theta}(1)$ for any $\theta \in \Theta$. For a fixed $\theta_0$ in...

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Give example of a countable collection of finite sets whose union is not finite

This is exercise 3.E from Elements of Real Analysis by Bartle. The exercise asks to give an example of a countable collection of finite sets whose union is not finite and I wanted to verify if my...

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Show that $\frac{1+z-\sqrt{z^2-6z+1}}{4}$ fits the Lagrangean framework

Let $S(z)$ be the OGF of bracketings. Show that the Lagrangean framework holds for $S(z)$.Remark: You can find the definition of Lagrangean framework below.From the Flajolet & Sedgewick book (p.81)...

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Calculate the upper sums Un and lower sums Ln,on a regular partition of the...

Calculate the upper sums $U_n$ and lower sums $L_n$, on a regular partition of the intervals, for the following integral:$$\int_1^2 \lfloor x\rfloor dx$$$$\Delta x=\frac{1}{n}$$And then I'm unsure as...

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Circular shift of a function.

Consider a function $f$ that maps real numbers to real numbers with domain $[-a,a]$. I would like to describe the circular shift of this function by an amount $\delta$ such that, if I shift the...

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Is this integral in its most simplified form?

The following integration $$F(x)= \int_{x}^{+\infty} \frac{t}{1+t^\alpha} dt$$ cannot be solved in general, however can be expressed when $\alpha=4$ as $$F(x)= 0.5 \text{tan}^{-1} (x^{-2}) $$it can...

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under what condition do we have $f(x)+g(y)=h(x+y)$?

Suppose we have functions $f(p_1,p_2,w_1)$ and $g(p_1,p_2,w_2)$. Under what condition do we have a function $h(p_1,p_2,w)=f(p_1,p_2,w_1)+g(p_1,p_2,w_2)$ where $w=w_1+w_2$?Or if we generalise this to...

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Is there a website that has all the special functions?

There are a lot of special functions, and I wonder if there is a website that collects all of them, similar to how the Encyclopedia of Triangle Centers collects information on triangle centers.Another...

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Topology of uniform convergence?

Stone starts with an arbitrary compact Hausdorff space X and considers the algebra C(X,R) of real-valued continuous functions on X, with the topology of uniform convergenceI am having a hard time...

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Constructing smooth paths between points in codomain

I have a differentiable non-bijective mapping f from $x \in R^T$ to $y = f(x) \in R^T$.Say I have some positions $x_s^*$ and $x_e^*$ with corresponding mappings $y_s*$ and $y_e^*$.Questions:I assume...

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Let a real measurable function $f$ map every open set to the whole real line....

Given $f:\mathbb{R}\rightarrow\mathbb{R}$ mapping each non-empty open set to the whole real line, is there always a set $A$ of measure zero such that the function $g:\mathbb{R}\rightarrow\mathbb{R}$...

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Equivalent definitions of affine function

For a function $f\colon\mathbb{R}^n\to\mathbb{R}$ the following two are equivalent\begin{align*}&\text{(i) there exist $a\in\mathbb{R}^n$, $b\in\mathbb{R}$ so that...

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Examining the function.

Given function: $$f(x)=|x+2|e^{-\frac{1}{|x|}}$$Find constants $a, b$ and $c$ such that $f(x)= ax +b+\frac{c}{x}+ \sigma(\frac{1}{x})$ when $x \rightarrow \infty$ and $x \rightarrow -\infty$?Examine...

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