Practice Claim 1 (9.2) - Tutorial 5 - Discrete Mathematics

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9 questions

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6 sample questions

Question 1.
Define cardinality.
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Think about how we measure the size of a collection.
Question 2.
What is an injective mapping?
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Consider how a one-to-one relationship works.
3Question 3.
What does cardinality measure?
- The size of a set
- The total number of distinct numbers
- The frequency of elements in a set
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Think about how we define the overall count of items.
4Question 4.
True or False: An injective mapping can map two different inputs to the same output.
- True
- False
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Reflect on the one-to-one relationship described in definitions.
Question 5.
Prove that the set of rational numbers is countably infinite.
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Structure your list carefully to ensure each fraction is included exactly once.
Question 6.
Show that removing one element from any infinite set leaves an infinite set.
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You can relate it to the counting of elements and their infinite nature.

5 more questions in this section. Enroll free to practise them all.