一、定义A与B的差集A-B={x|x∈A且x不属于B}。(1)设全集为U,请用集合的交、并、补运算表示A-B与B-A; 定义差集A-B={x|x∈A,且x?B},现有三个集合A、B...
\u8bbeA\uff0cB\u662f\u4e24\u4e2a\u975e\u7a7a\u96c6\u5408\uff0c\u5b9a\u4e49A\u4e0eB\u7684\u5dee\u96c6A-B={x|x\u2208A\uff0c\u4e14x?B}\uff0e\uff081\uff09\u8bd5\u4e3e\u51fa\u4e24\u4e2a\u6570\u96c6\uff0c\u6c42\u5b83\u4eec\u7684\u5dee\u96c6\uff1b\uff082\uff09\uff081\uff09\u5982A={1\uff0c2\uff0c3}\uff0cB={2\uff0c3\uff0c4}\u5219A-B={1}\uff082\uff09\u4e0d\u4e00\u5b9a\u76f8\u7b49\u7531\uff081\uff09B-A={4}\uff0c\u800cA-B={1}\uff0c\u6545A-B\u2260B-A\u53c8\u5982\uff0cA=B={1\uff0c2\uff0c3}\u65f6\uff0cA-B=?\uff0cB-A=?\u6b64\u65f6A-B=B-A\u6545A-B\u4e0eB-A\u4e0d\u4e00\u5b9a\u76f8\u7b49\uff0e
\u2235A-B={x|x\u2208A\uff0c\u4e14x?B}\uff0c\u5373A-B\u662f\u96c6\u5408A\u4e2d\u7684\u5143\u7d20\u53bb\u6389A\u2229B \u8bb0\u4f5c\u96c6\u5408D\u5982\u56fe\u6240\u793a\u2234\u96c6\u5408C-\uff08A-B\uff09\u5c31\u662fC\u4e2d\u7684\u5143\u7d20\u53bb\u6389\u96c6\u5408C\u2229D\u6545\u9009A
(1) A-B=A∩(cuB) B-A=B∩(cuA)2)设A={0,1,2,3},B={1,2,4},A-B={0,3}, B-A={4}.
已知A={x|x>4},B={x||x|<6},(1)A-B={x|x》6}, A-(A-B)={x|4<x<6}
B-A={x|-6<x《4}, B-(B-A)={x|4<x<6},而A∩B={x|4<x<6},
结论: A-(A-B)=B-(B-A)=A∩B。
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绛旓細瑙o細锛1锛堿={1,2,3}锛孊={2,4} A-B={1,3}锛孊-A={4} 锛2锛変笉鐩哥瓑锛屼笂闈㈢殑渚嬪瓙鍗冲彲 锛3锛夊疄闄呬笂A-B=A鈭〣鐨勮ˉ闆 鎵浠 A-(A-B)=A鈭〣锛屽悓鏍稡-(B-A)=A鈭〣 鎵浠 A-(A-B)=B-(B-A)={x|4<x<6}
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