【简答题】【消耗次数:1】
设 Ri 是 X 上的二元关系, 对于 x∈X 定义集合Ri(x)={y|xRiy}. 如果 X={-4, -3, -2, -1, 0, 1, 2, 3, 4}, 且令R1={|x, y∈Xùxy},则求R1(1)。
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【简答题】 设 Ri 是 X 上的二元关系, 对于 x∈X 定义集合Ri(x)={y|xRiy}. 如果 X={-4, -3, -2, -1, 0, 1, 2, 3, 4}, 且令R2={|x, y∈Xùy-1y+2},则求R2(-1)。
【简答题】 设 Ri 是 X 上的二元关系, 对于 x∈X 定义集合Ri(x)={y|xRiy}. 如果 X={-4, -3, -2, -1, 0, 1, 2, 3, 4}, 且令R3={|x, y∈Xùx2≤y},则求R3(3)。
【判断题】 设 Ri 是 X 上的二元关系, 对于 x∈X 定义集合Ri(x)={y|xRiy}. 如果 X={-4, -3, -2, -1, 0, 1, 2, 3, 4}, 且令R2={|x, y∈Xùy-1y+2},则R2(-1) ={ -2, -1}.
①  正确
②  错误
【简答题】 设 Ri 是 X 上的二元关系, 对于 x∈X 定义集合Ri(x)={y|xRiy}. 如果 X={-4, -3, -2, -1, 0, 1, 2, 3, 4}, 且令R2={|x, y∈Xùy-1y+2},则R2(-1) =[填空1]
【单选题】 设 Ri 是 X 上的二元关系, 对于 x∈X 定义集合Ri(x)={y|xRiy}. 如果 X={-4, -3, -2, -1, 0, 1, 2, 3, 4}, 且令R1={x, y|x, y∈X<img class=jc-formula style=vertical-align: middle; src=https://huaweicloudobs.ahjxjy.cn/D50FEE5510C853C83F78D440017D8E6B.png data-tex=\wedge />xy},则R1(1) =
①  {1,2,3,4};
②  {2,3,4};
③  { -1,0};
④  { -2, -1}。
【单选题】 设 Ri 是 X 上的二元关系, 对于 x∈X 定义集合Ri(x)={y|xRiy}. 如果 X={-4, -3, -2, -1, 0, 1, 2, 3, 4}, 且令R1={x, y|x, y∈X<img class=jc-formula style=vertical-align: middle; src=https://huaweicloudobs.ahjxjy.cn/D50FEE5510C853C83F78D440017D8E6B.png data-tex=\wedge />xy},则R1(0) =
①  {1,2,3,4};
②  {2,3,4};
③  { -1,0};
④  { -2, -1}。
【单选题】 设 Ri 是 X 上的二元关系, 对于 x∈X 定义集合Ri(x)={y|xRiy}. 如果 X={-4, -3, -2, -1, 0, 1, 2, 3, 4}, 且令R2={x, y|x, y∈X<img class=jc-formula style=vertical-align: middle; src=https://huaweicloudobs.ahjxjy.cn/D50FEE5510C853C83F78D440017D8E6B.png data-tex=\wedge />y-1y+2},则R2(-1) =
①  {1,2,3,4};
②  {2,3,4};
③  { -1,0};
④  { -2, -1}。
【单选题】 设 Ri 是 X 上的二元关系, 对于 x∈X 定义集合Ri(x)={y|xRiy}. 如果 X={-4, -3, -2, -1, 0, 1, 2, 3, 4}, 且令R2={x, y|x, y∈X<img class=jc-formula style=vertical-align: middle; src=https://huaweicloudobs.ahjxjy.cn/D50FEE5510C853C83F78D440017D8E6B.png data-tex=\wedge />y-1y+2},则R2(0) =
①  {1,2,3,4};
②  {2,3,4};
③  { -1,0};
④  { -2, -1}。
【简答题】 设 A={1, 2, 4, 6}, 分别求关系 R={|x, y∈Aùx+y12}、{|x, y∈Aù|x-y|=1}、{|x, y∈Aùx/y∈A}和{|x, y∈Aùy 为素数}。
【单选题】 设 Ri 是 X 上的二元关系, 对于 x∈X 定义集合Ri(x)={y|xRiy}. 如果 X={-4, -3, -2, -1, 0, 1, 2, 3, 4}, 且令R3={x, y|x, y∈X<img class=jc-formula style=vertical-align: middle; src=https://huaweicloudobs.ahjxjy.cn/D50FEE5510C853C83F78D440017D8E6B.png data-tex=\wedge /><img class=jc-formula style=vertical-align: middle; src=https://huaweicloudobs.ahjxjy.cn/0305FF21DAA4ED8519EFCEDC63EB7EC5.png data-tex={ x }^{ 2 }/>≤y},则R3(3) =
①  {0};
②  {1};
③  <img class=jc-formula style=vertical-align: middle; src=https://huaweicloudobs.ahjxjy.cn/E566BCAE77E174BC709DE66706F41CEC.png data-tex=\emptyset />;
④  { -1}。
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