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Basic set theory question 
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#1
Oct304, 08:20 PM

P: 143

ok, find the intersection of i=1 to infinitie of A(i).
A(i) = [0, to 1/i]. I dont understand what it is asking. what do they mean to find the intersection of that? and what if A(i) = [0, 1/n) 


#2
Oct304, 10:01 PM

P: 1,572

To use mathematicasque notation, Intersect[A(i), {i,1,oo}] is the set of all points in each A(i). There's only one point in all A(i)'s: 0. Therefore the intersection is {0}. Same with the second one. But if they made it (0,1/i) then it would be empty.



#3
Oct304, 10:04 PM

P: 1,367

Do you mean:
[tex]\bigcap_{i=1}^{\infty} A(i)[/tex] where A(i) = [0, 1/i]? Wouldn't the answer be {0}? 


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