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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 characteristics of finite sets.
Question 2
Easy
Is the set of prime numbers countable?
💡 Hint: Can you list them in order?
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 defines a countable set?
- It must have a finite number of elements.
- It can be either finite or have the same cardinality as positive integers.
- It cannot have an infinite number of elements.
💡 Hint: Remember the definition of countability.
Question 2
Which set is not countable?
- The set of natural numbers.
- The set of real numbers.
- The set of odd numbers.
💡 Hint: Think about how many numbers are between any two integers.
Solve 1 more question and get performance evaluation
Challenge Problems
Push your limits with challenges.
Question 1
Determine if the set of all even integers is countable and justify your answer.
💡 Hint: Consider the way they pair with positive integers.
Question 2
Show whether the set of all subsets of natural numbers is countable.
💡 Hint: Think about how many subsets can exist versus elements.
Challenge and get performance evaluation