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Practice Questions
Test your understanding with targeted questions related to the topic.
Question 1
Easy
Define a countable set.
💡 Hint: Think about the types of numbers you can count.
Question 2
Easy
What is a bijection?
💡 Hint: Consider how each element from one set relates to the other.
Practice 4 more questions and get performance evaluation
Interactive Quizzes
Engage in quick quizzes to reinforce what you've learned and check your comprehension.
Question 1
What is a countable set?
- A set that is finite and can’t be listed
- A set with more than one element only
- A set that can be put into one-to-one correspondence with positive integers
💡 Hint: Focus on how we understand counting beyond finite numbers.
Question 2
True or False: The set of real numbers is countable.
- True
- False
💡 Hint: Recall the characteristics of uncountable sets.
Solve 1 more question and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
Prove that the set of natural numbers is countable by establishing a bijection with the integers.
💡 Hint: Consider how you can start pairing from 0.
Question 2
Show why the set of rational numbers is countable.
💡 Hint: Think about how to organize and sequence pairs.
Challenge and get performance evaluation