Let X = R and A = {disjoint union of the intervals of the form (a,...

Let X = R and A = {disjoint union of the intervals of the form (a, b], (−∞, b] and (a, + ∞)}. Prove that A is an algebra but not a σ-algebra.

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Expert Solution

Here is the answer.

Here we assume that X and empty set includes in A.

By construction of A it is clear that finite union of elements of A belongs to A.

Colby Messinger answered 10 months ago

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