Practice Cardinality Of Finite Sets (3.1) - Countable and Uncountable Sets

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6 sample questions

Question 1.
What is the cardinality of the set {Cat, Dog, Fish}?
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Count the number of elements.
Question 2.
True or false: |{Apple, Banana}| = |{1, 2, 3}?
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Compare the number of elements in each set.
3Question 3.
What does the notation |X| represent?
- The dimensions of set X
- The cardinality of set X
- The elements in set X
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Think of cardinality as counting.
4Question 4.
True or False: A bijection implies that the two sets have the same number of elements.
- True
- False
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Remember the definition of bijection.
Question 5.
Demonstrate why the set of all even integers is countable and establish a bijection to the positive integers.
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Consider how each positive integer relates to an even integer.
Question 6.
Find all the possible bijections between the sets A = {1, 2} and B = {x, y}.
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Count how many ways to pair elements uniquely.

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