Is this function uniformly continuous?

In summary, uniform continuity is a mathematical concept that describes the behavior of a function. It is a stronger condition than regular continuity and requires that the function is continuous at every point in its domain when extended to include all real numbers. To be considered uniformly continuous, a function must be continuous at every point in its domain and have a consistent rate of change between points. This can be proven using the ε-δ definition of uniform continuity. Not all continuous functions are uniformly continuous, as some may have unbounded rates of change.
  • #1
robertdeniro
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Homework Statement


we have 2 metric spaces (X, d) and (Y, d')

given:
1) A is a dense subset of X
2) Y is complete
3) there is a uniformly continuous function f: A->Y

let g: X->Y be the extension of f
that is, g(x)=f(x), for all x in A

is g uniformly continuous?

Homework Equations


The Attempt at a Solution



not sure where to start...
 
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  • #2
You could start by proving that such an extension exists and is unique. How would you define g?
 

FAQ: Is this function uniformly continuous?

What is uniform continuity?

Uniform continuity is a mathematical concept that describes the behavior of a function. A function is considered uniformly continuous if the amount of change in the output values is proportional to the amount of change in the input values, regardless of where on the function's domain the changes occur.

How is uniform continuity different from regular continuity?

Uniform continuity is a stronger condition than regular continuity. While regular continuity only requires that the function is continuous at every point in its domain, uniform continuity requires that the function is also continuous at every point in its domain when the domain is extended to include all real numbers.

What properties must a function have to be considered uniformly continuous?

A function must be continuous at every point in its domain, and its rate of change must not vary significantly between points in its domain. In other words, as the input values get closer to each other, the output values must also get closer together at a consistent rate.

How do you prove that a function is uniformly continuous?

To prove that a function is uniformly continuous, you must show that for any given positive number ε, there exists a positive number δ such that whenever two points in the function's domain are within δ units of each other, their corresponding output values are within ε units of each other. This can be done using the ε-δ definition of uniform continuity.

Are all continuous functions also uniformly continuous?

No, not all continuous functions are uniformly continuous. While all uniformly continuous functions are also continuous, the reverse is not always true. For example, the function f(x) = 1/x is continuous on its domain of (0,∞), but it is not uniformly continuous because its rate of change becomes unbounded as x approaches 0.

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