Practice Examples Of Countably Finite Sets (3.6) - Countable and Uncountable Sets

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6 sample questions

Question 1.
What is a countable set?
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Think about the definition used in determining if a set is countable.
Question 2.
Give an example of a finite countable set.
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Consider a set with a limited number of elements.
3Question 3.
What defines a countably infinite set?
- It is finite
- It has a bijection with positive integers
- It has no elements
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Remember the characteristics of countable sets.
4Question 4.
Is the set of integers countable?
- True
- False
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Think about how you would list both integers and positives.
Question 5.
Demonstrate a bijection between the set of natural numbers and the set of rational numbers.
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Consider how to systematically list all possible fractions.
Question 6.
Can you create a map for the relation between the set of all integers and the set of even integers?
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Think about how one integer corresponds to one even integer.

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