【简答题】【消耗次数：1】
设 R={0,10,20,31,21,32,3}，求关系R的逆关系R-1。
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相关题目
【简答题】
设 R={0,10,20,31,21,32,3}，求关系R的二次合成R○R。
【简答题】
设 R={0,10,20,31,21,32,3}，求关系R在{0,1}上的限制R?{0,1}。
【简答题】
设 R={0,10,20,31,21,32,3}，求{1,2}在关系R下的像R[{1,2}]。
【单选题】
设 R={0,10,20,31,21,32,3}，则关系R的二次合成R○R等于：
①
{0,20,31,3
②
{1,02,03,02,13,13,2
③
{0,10,20,31,21,3
④
{2,3}.
【单选题】
设 R={0,10,20,31,21,32,3}，则关系R在{0,1}上的限制R?{0,1}等于：
①
{0,20,31,3
②
{1,02,03,02,13,13,2
③
{0,10,20,31,21,3
④
{2,3}.
【单选题】
设 R={0,10,20,31,21,32,3}，则{1,2}在关系R下的像R[{1,2}]等于：
①
{0,20,31,3
②
{1,02,03,02,13,13,2
③
{0,10,20,31,21,3
④
{2,3}.
【简答题】
设 R={0,10,20,31,21,32,3}，则关系R在{0,1}上的限制R?{0,1}等于：[填空1]
【单选题】
设 R={0,10,20,31,21,32,3}，则关系R的逆关系<img class=jc-formula style=vertical-align: middle; src=https://huaweicloudobs.ahjxjy.cn/C60082AF1C54FFA5A63D2879E701543A.png data-tex={ R }^{ -1 }/>等于：
①
{0,20,31,3
②
{1,02,03,02,13,13,2
③
{0,10,20,31,21,3
④
{2,3}.
【简答题】
设 A={a,b,c,d}, A上的关系R1={,,}，R2={,,,}，求合成关系R1○R2。
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more tall
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①
saw
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has seen
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had seen
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was seeing