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Homework Help: Digraphs Help

  1. Feb 13, 2012 #1
    1. The problem statement, all variables and given/known data

    Construct a digraph for the relations: (i) being a square of and (ii) being divisible without remainder by on the set {1, 2, 3, 4, 5}.

    2. Relevant equations



    3. The attempt at a solution

    {<1,2>, <1,3>, <1,4>, <1,5>, <2,3>, <2,4>, <2,5>, <3,4>, <3,5>, <4,5>}

    I am completely lost and do not even know where to begin. Help!
     
  2. jcsd
  3. Feb 13, 2012 #2
    first get the relations defined by them. for example if I understand (i), (x,y) belongs to the
    relation R if y is square of x (x and y in the given set), then we can define the relation R as

    [tex]R=\{(1,1),(2,4)\} [/tex]

    Now to construct the digraph (or directed graph), refer to this link.
    http://www.cs.odu.edu/~toida/nerzic/level-a/digraph/definition.html

    It shows how to do this....And do similarly for the second relation
     
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