Exercise 5. Show that the intersection of dense sets need not be dense, but the inter-...

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Exercise 5. Show that the intersection of dense sets need not be dense, but the inter- section of two open dense sets is alwa

math Advanced-Math

Answer 1

Answer #1

Let IR be the topological space with usual topology. then Q and IR-Q both are dense subsets of IR but QnCIRIQ) = 0, which is

Answer 2

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