Constructing a Digraph: {1,2,3,4,5}

  • Thread starter Thread starter bird34
  • Start date Start date
bird34
Messages
7
Reaction score
0

Homework Statement



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}.

Homework Equations





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!
 
Physics news on Phys.org
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

R=\{(1,1),(2,4)\}

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
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
Back
Top