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5 votes
Complete all parts of the problem.

Complete all parts of the problem.-example-1
User Notgiorgi
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1 Answer

5 votes

(a)


\bigcup\limits_(i=1)^7R_i=R_1=\boxed{[1,2]}

(b)


\bigcap\limits_(i=1)^7R_i=R_7=\boxed{\left[1,\frac87\right]}

(c) No, because no two sets are disjoint. Why? Each of the
R_i contain the endpoint 1, so at the very least,
\{1\}\subseteq R_i\cup R_j for
i\\eq j.

(d)


\bigcup\limits_(i=1)^nR_i=R_1=\boxed{[1,2]}

(e)


\bigcap\limits_(i=1)^nR_i=R_n=\boxed{\left[1,\frac{n+1}n\right]}

(f)


\bigcup\limits_(i=1)^\infty R_i=R_1=\boxed{[1,2]}

because as i gets larger, the set
R_i gets smaller. The infinite union will be equivalent to the largest set in the family of sets.

(g)


\bigcap\limits_(i=1)^\infty R_i=\boxed{\{1\}}

because 1 + 1/n converges to 1 as n goes to infinity, so
R_i converges to the singleton set {1} as i goes to infinity.

User SimpleBinary
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