Recent questions tagged relations

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R isiff $R ^{-1}$ isTotal?a function?a surjection?an injection?a bijection?Fill in the entries in the table.
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What is the number of relations S over set {0,1,2,3} such that (x,y) $\epsilon$ S $\Rightarrow x = y$ ? Thanks.
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Consider the following relation:$R={(x,y)| y=x^i, ∃ “i” in Z }$R isi) Reflexiveii) Symmetriciii) Anti symmetriciv) TransitiveThanks!
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131
Answer has R4 and E2 merged, I cant visualize how? what will be primary key? What will be other attributes?
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133
How to take composition of a Relation? here used concept of function but when to go with the transitivity rule concept as mentioned below?Please clarify in general when t...
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139
Ans:BSymmetric closure of R1. It is symmetric2. It contains R3.Minimal relation satisfying 1 and 2If we consider B, then condition 2 may be violated. Therefore I think th...
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Find a positive integer n such that given any set N with size|N|=n, then the number of reflexive relations on N is equal to number of symmetric relations on N______?i am ...
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R is a relation define on set A = {1,2,3}. The R is symmetric, transitive and irreflexive. Then |R| =
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Online Site For practicing Relational Algebrahttps://dbis-uibk.github.io/relax/calc.htm