Show Uniform Convergence of Sequence of Functions on Set X

In summary, a uniform metric is a metric obtained from the uniform norm, where the distance between two functions is the maximum difference between their values at any point in the set.
  • #1
tomboi03
77
0
Let X be a set, and let fn : X [tex]\rightarrow[/tex] R be a sequence of functions. Let p be the uniform metric on the space Rx. Show that the sequence (fn) converges uniformly to the function f : X [tex]\rightarrow[/tex] R if and only if the sequence (fn) converges to f as elements of the metric space
(RX, p)

I'm not sure how to do this problem...

Can someone help me out?

Thanks!
 
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  • #2
Where are you stuck? Start by writing down all the relevant definitions (uniform metric, uniform convergence, convergence in metric spaces) and you will be almost done.
 
  • #3
please define what is mean't by " uniform metric"
 
  • #4
de_brook said:
please define what is mean't by " uniform metric"

It's the metric obtained from the http://en.wikipedia.org/wiki/Uniform_norm" , so

[tex]d(f,g)=\sup_{x\in X}|f(x)-g(x)|[/tex]

where [tex]f,g:X\to\mathbb{R}[/tex].
 
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What is uniform convergence of a sequence of functions?

Uniform convergence is a type of convergence where the convergence rate is independent of the point in the domain. In simpler terms, it means that the sequence of functions converges to the same limit at the same rate regardless of the point in the domain.

What is the significance of uniform convergence?

Uniform convergence is important because it guarantees that the limit function is continuous and that the sequence of functions can be manipulated algebraically without changing the limit. This allows for easier analysis and computation of the limit function.

What is the difference between pointwise and uniform convergence?

The main difference between pointwise and uniform convergence is the rate at which the sequence of functions converges. Pointwise convergence only guarantees convergence at each individual point in the domain, while uniform convergence guarantees convergence at all points in the domain simultaneously.

How is uniform convergence of a sequence of functions proven?

To show uniform convergence of a sequence of functions on a set X, we must prove that the sequence of functions converges uniformly on that set. This is typically done by showing that the sequence of functions satisfies the Cauchy criterion for uniform convergence, or by using other established criteria and theorems.

What are some examples of sets where uniform convergence can be shown?

Uniform convergence can be shown on a variety of sets, including closed and bounded intervals, compact sets, and any set where the functions are uniformly bounded and equicontinuous. Examples of these types of sets include the interval [0,1], the unit circle, and the closed and bounded set [a,b].

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