集合A={3,2a},B={a,b},若A∩B={2},则A∪B=______.
题型:填空题难度:一般来源:泉州模拟
集合A={3,2a},B={a,b},若A∩B={2},则A∪B=______. |
答案
根据题意,若A∩B={2},则2∈A,2∈B, 而已知A={3,2a},则必有2a=2, 故a=1, 又由2∈B,且a=1 则b=2, 故A∪B={1,2,3}, 故答案为{1,2,3}. |
举一反三
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