Competition problem — Combinatorics

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Combinatorics Difficulty 1.9 Junior Find the answer

Given $U=\{1,2,3,4\}$ , $A=\{1,3,4\}$ , $B=\{2,3,4\}$ , then $C_U(A\cup B)=$

Pick one

Solution

Since $A\cup B=\{1,2,3,4\}$ ,
and $U=\{1,2,3,4\}$ ,
therefore $C_U(A\cup B)=\emptyset$
Hence, the correct option is $\boxed{C}$ .

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Source: NuminaMath-1.5, licensed Apache-2.0. Statement and solution reproduced as published; topic and difficulty added by this site.