Practice Question 10: Relations And Functions (2.6) - Introduction - Discrete Mathematics

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6 sample questions

Question 1.
What does reflexivity mean in the context of equivalence relations?
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Think of what happens when you compare an element to itself.
Question 2.
Define a surjective function in simple terms.
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Consider how each element in the output set is associated.
3Question 3.
What characterizes a bijective function?
- It is injective
- It is surjective
- Both injective and surjective
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Think about the definitions of injective and surjective.
4Question 4.
True or False: A surjective function guarantees that all outputs are unique.
- True
- False
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Consider mappings where elements can overlap.
Question 5.
Determine and justify whether the relation defined on the set {1, 2, 3} with pairs {(1, 2), (2, 1), (2, 3)} is an equivalence relation.
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Examine each of the equivalence relation properties separately.
Question 6.
Calculate the number of surjective functions from a set with 3 distinct elements to a set with 2 distinct elements, employing the Stirling function.
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Break it down using partitions and consider permutations!

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