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

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.
 
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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.
 
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There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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