Is this function in the L^2(0,1) space for certain values of C_1 and C_2?

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Discussion Overview

The discussion revolves around the characterization of a specific function, ##f(x)=x^{-1}(C_1+C_2 \ln x)##, and whether it belongs to the space ##L^2(0,1)## for certain values of constants ##C_1## and ##C_2##. Participants explore the implications of the integral of the function and its convergence properties, as well as tangential inquiries into Lebesgue differentiation and integration.

Discussion Character

  • Exploratory
  • Technical explanation
  • Debate/contested
  • Mathematical reasoning

Main Points Raised

  • One participant states that for a function to be in ##L^2(0,1)##, the integral must be finite, raising the question of how to evaluate this for the given function.
  • Another participant asserts that the integral diverges at ##x=0## unless both constants ##C_1## and ##C_2## are zero, suggesting that the function cannot be in ##L^2(0,1)## under those conditions.
  • Several participants inquire about the relationship between Lebesgue differentiation and Lebesgue integration, with some expressing unfamiliarity with the term "Lebesgue differentiation."
  • Links to external resources on Lebesgue differentiation and its theorems are provided, with participants acknowledging the usefulness of these references.

Areas of Agreement / Disagreement

There is disagreement regarding the integrability of the function in question, with one participant claiming it diverges while another seeks clarification on the evaluation of the integral. The discussion on Lebesgue differentiation remains unresolved, with multiple participants seeking definitions and explanations.

Contextual Notes

The discussion includes assumptions about the behavior of the function near ##x=0##, which are not fully explored. The relationship between Lebesgue differentiation and integration is also not clearly defined, indicating a need for further clarification.

Who May Find This Useful

Readers interested in functional analysis, particularly in the context of Lebesgue spaces, as well as those exploring measure theory and integration techniques may find this discussion relevant.

LagrangeEuler
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If some function is element of space ##L^2(0,1)## then
\int^1_0|f(x)|^2dx< \infty. What in the case when it is not so simple to calculate this integral. For example ##f(x)=x^{-1}(C_1+C_2 \ln x)##. How to find is it this function in ##L^2(0,1)## for some ##C_1,C_2##?
 
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It is never (other than both constants = 0). Integral diverges at x=0.
 
Please help me to define Relation between Lebesgue Differentiation and Lebesgue integration?
 
Amal Chacko said:
Please help me to define Relation between Lebesgue Differentiation and Lebesgue integration?
I have never seen the term Lebesgue differentiation. Lebesgue integration is a theory of integration based on measure theory.
 
Ah, yes, Hawkeye's link is clearly better, more direct than mine.
 

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