Practice Part F: Neither Reflexive Nor Irreflexive Relations (21.4.6)

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6 sample questions

Question 1.
Define a reflexive relation.
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Think about pairs (x, x) for elements in the set.
Question 2.
What makes a relation irreflexive?
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Consider the opposite of reflexive.
3Question 3.
What must a reflexive relation always include?
- (x
- y)
- (a
- b)
- (a
- a)
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Link to the definition of reflexivity.
4Question 4.
Is it possible for a relation to be both reflexive and irreflexive?
- True
- False
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Consider the implications of both terms.
Question 5.
Prove that a set relation cannot be both reflexive and irreflexive by using a set S of size n.
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Focus on defining elemental constraints.
Question 6.
Given a relation is defined such that for every set element, at least one diagonal element exists while excluding some, how would you categorize that set?
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Consider pair distributions.

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