在①1⊆{0,1,2,3};②{1}∈{0,1,2,3};③{0,1,2,3}⊆{0,1,2,3};④∅⊊{0},上述四个关系中,错误的个数是( )A.1个B
题型:单选题难度:简单来源:不详
在①1⊆{0,1,2,3};②{1}∈{0,1,2,3};③{0,1,2,3}⊆{0,1,2,3};④∅⊊{0},上述四个关系中,错误的个数是( ) |
答案
①1∈{0,1,2,3},故①错误; ②{1}⊆{0,1,2,3},故②错误; ③{0,1,2,3}⊆{0,1,2,3},故③正确; ④∅⊊{0},故④正确. 故选B. |
举一反三
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