Fourier transform of f'(x), lebesgue integrability

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SUMMARY

The discussion focuses on the properties of the function F(x) defined as the integral of an L-integrable function f over the interval from 0 to x. It is established that F(x) is continuous due to the properties of Lebesgue integrability. Additionally, it is concluded that if F is L-integrable, then the limit of F(x) as x approaches ±∞ equals 0. The Dominated Convergence Theorem is referenced as a potential method for proving this limit, although some participants express confusion regarding the dominating function.

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  • Understanding of Lebesgue integrability
  • Familiarity with the Dominated Convergence Theorem
  • Knowledge of properties of continuous functions
  • Basic concepts of limits in real analysis
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  • Study the Dominated Convergence Theorem in detail
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  • Review the continuity of integrals of Lebesgue integrable functions
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demonelite123
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a) let f be L-integrable on R. show that F(x) = integral (from 0 to x) f(t)dt is continuous.
b) show that if F is L-integrable, then lim (as x approaches +/-∞) of F(x) = 0.

i am a little stuck on part b). i am trying to use the dominated convergence theorem but i am a bit confused on what function is dominating what. since F is L-integrable it can be written as an infinite sum of L integrable functions but it is not clear to me how i can use that to show that the limit as x approaches +/- infinite of F(x) = 0. is there a better way to think of F(x) that can help me prove this fact?
 
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