Examples of Pointwise Convergence of Integrable Functions to Non-Integrable

In summary, pointwise convergence of integrable functions to non-integrable refers to a sequence of functions approaching a non-integrable function at every point in a given domain. This concept is important for understanding the behavior and properties of the non-integrable function. It is possible for a sequence of integrable functions to converge pointwise to a non-integrable function, such as the example of f_n(x) = x^n on the interval [0,1]. Pointwise convergence is different from uniform convergence in that it only requires convergence at every point in the domain, while uniform convergence requires uniform convergence on the entire domain.
  • #1
irresistible
15
0
hey guys,
Any one can think of any examples ?
Of a sequence of integrable functions{fn} on [0,1] that converges pointwise to a non-integrable function f:[0,1] --> R
??
 
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  • #2


fn=1/x for x>1/n, fn=n for x<1/n.
 
  • #3


mathman, I don't believe that function converges pointwise (specifically at 0). Setting fn(0) = 0 will fix that, though.
 

FAQ: Examples of Pointwise Convergence of Integrable Functions to Non-Integrable

What is pointwise convergence of integrable functions to non-integrable?

Pointwise convergence refers to the concept of a sequence of functions approaching a specific function at every point in a given domain. In the case of integrable functions, this means that the sequence of functions approaches a non-integrable function at every point in the domain.

Why is pointwise convergence of integrable functions to non-integrable important?

This concept is important because it allows us to study the behavior of a sequence of functions and understand how it approaches a non-integrable function. It also helps us to determine the properties of the non-integrable function in terms of its integrability.

Can a sequence of integrable functions converge pointwise to a non-integrable function?

Yes, it is possible for a sequence of integrable functions to converge pointwise to a non-integrable function. This means that at every point in the domain, the sequence of functions approaches the non-integrable function.

What are some examples of pointwise convergence of integrable functions to non-integrable?

One example is the sequence of functions defined by f_n(x) = x^n on the interval [0,1]. This sequence converges pointwise to the function f(x) = 0, which is not integrable on the given interval.

How is pointwise convergence of integrable functions to non-integrable different from uniform convergence?

Pointwise convergence is different from uniform convergence in that it only requires that the sequence of functions approaches the non-integrable function at every point in the domain, whereas uniform convergence requires that the sequence of functions approaches the non-integrable function uniformly on the entire domain.

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