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

In summary, the conversation discusses how to show that the set S, defined as {(x,y): 0 <= y <= g(x), a <= x <= b}, is rectifiable. It is mentioned that one way to approach this is by showing that S is bounded and that the boundary of S has measure zero. The issue at hand is proving that S is bounded, given that g is only continuous almost everywhere and it is uncertain if g is bounded on [a,b]. The definition of rectifiable is also mentioned, stating that a set S is rectifiable if its volume can be calculated. However, it is later mentioned that the problem has been solved.
  • #1
johnson12
18
0
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.
 
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  • #2
forgot to mention the definition of rectifiable here: a (bounded) set S is rectifiable if

[tex]\int_{S} 1[/tex] exists. (so it has volume.)update: PROBLEM HAS BEEN SOLVED.
 
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FAQ: Is the Set Defined by a Continuous Almost Everywhere Function Rectifiable?

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Multivariable calculus is a branch of mathematics that deals with functions of multiple variables and their derivatives. It extends the concepts of single variable calculus to functions with more than one independent variable.

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Multivariable calculus has numerous applications in fields such as physics, engineering, economics, and computer science. It is used to study motion in three-dimensional space, optimize complex systems, and model relationships between multiple variables.

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The main techniques used in multivariable calculus include partial derivatives, multiple integrals, and vector calculus. These techniques are used to analyze functions of multiple variables and their behavior in three-dimensional space.

What is the difference between multivariable calculus and single variable calculus?

The main difference between multivariable calculus and single variable calculus is that multivariable calculus deals with functions of multiple variables, while single variable calculus only deals with functions of one variable. Multivariable calculus also involves the use of vectors and vector calculus, which are not typically used in single variable calculus.

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Some common challenges in learning multivariable calculus include understanding the concept of partial derivatives, visualizing functions in three-dimensional space, and mastering the use of vectors and vector calculus. It can also be challenging to apply the concepts of multivariable calculus to real-world problems.

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