Is the Set Defined by a Continuous Almost Everywhere Function Rectifiable?

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SUMMARY

The discussion centers on the rectifiability of the set S defined by a continuous almost everywhere function g: [a,b] -> R, where g(x) > 0 on [a,b]. It concludes that S is rectifiable by demonstrating that it is bounded and that its boundary has measure zero. The key to the solution lies in establishing the boundedness of g on the interval [a,b], which was initially a point of confusion. The problem has been resolved with the understanding that the integral of the characteristic function over S exists, confirming its rectifiability.

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  • Understanding of rectifiable sets in measure theory
  • Knowledge of continuous functions and their properties
  • Familiarity with the concept of measure zero
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  • Study the properties of rectifiable sets in measure theory
  • Learn about functions that are continuous almost everywhere
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johnson12
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let g:[a,b] -> R be a function that is continuous almost everywhere. assume that g(x) > 0 on [a,b]. Show that the set
S = { (x,y): 0 <= y <= g(x) , a <= x <= b} is rectifiable.

One way to attack it, is to show that S is bounded and boundary of S has measure zero. the problem I am having is how to show that S is bounded, since g is continuous a.e. I don't now whether or not g is bounded on [a,b].

any comments at all are strongly appreciated, thanks.
 
Last edited:
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forgot to mention the definition of rectifiable here: a (bounded) set S is rectifiable if

\int_{S} 1 exists. (so it has volume.)update: PROBLEM HAS BEEN SOLVED.
 
Last edited:

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