问题
填空题
已知A={x|x为矩形},B={x|x为菱形},则A∩B=______.
答案
∵A={x|x为矩形},∴其元素的几何特征是有一个角为直角的平行四边形,
∵B={x|x为菱形},∴其元素的几何特征是邻边相等的平行四边形,
由交集的性质,A∩B中元素的特征是有一个角是直角且邻边相等的平行四边形,这样的图形是正方形,
故A∩B={x|x为正方形}
故答案为 {x|x为正方形}
已知A={x|x为矩形},B={x|x为菱形},则A∩B=______.
∵A={x|x为矩形},∴其元素的几何特征是有一个角为直角的平行四边形,
∵B={x|x为菱形},∴其元素的几何特征是邻边相等的平行四边形,
由交集的性质,A∩B中元素的特征是有一个角是直角且邻边相等的平行四边形,这样的图形是正方形,
故A∩B={x|x为正方形}
故答案为 {x|x为正方形}
阅读理解。 | ||||
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