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What is mutually disjoint sets?

I know it has something to do with subsets but I don't know for sure.

AlexR
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user4744409
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1 Answers1

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Let $\mathscr{A}$ be a family of sets. We say that the sets in $\mathscr{A}$ are mutually disjoint if no two of them have any elements in common. In other words, if $A,B\in\mathscr{A}$, and $A\ne B$, then $A\cap B=\varnothing$. Another term that means the same thing is pairwise disjoint.

In pictorial terms, if you make a Venn diagram of the sets, you’ll have a bunch of non-overlapping circles.

Brian M. Scott
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