Question about integrable functions

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The discussion addresses the properties of nonnegative Lebesgue measurable functions, specifically those supported on the interval [0,1]. It concludes that a function \( f \) with an infinite integral over this interval does not necessarily imply that the set \( E = \{ x \in [0,1] : f(x) = \infty \} \) has positive Lebesgue measure. The example provided is the function \( f(x) = 1/x \) for \( x \in (0,1] \) and a defined value at \( x = 0 \), illustrating that the set can have zero measure despite the infinite integral.

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Suppose you have a nonnegative Lebesgue measurable function supported on [tex][0,1][/tex] such that [tex]\int_0^1 f = \infty[/tex]. Does this mean that the set [tex]E = \{ x\in [0,1] : f(x) = \infty \}[/tex] has positive Lebesgue measure?
 
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No. Consider the function [itex]f\left(x\right)=1/x[/itex], and whatever value you want at x = 0.
 

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