If U = {1, 2, 3, 4, 5} and Aᶜ = {2, 5}, what is A ∩ Aᶜ?
Answer and explanation
Correct answer: ∅
By definition, Aᶜ consists of the elements of U that are not members of A. Thus A and Aᶜ are disjoint sets: they cannot have a common element. This gives the universal identity A ∩ Aᶜ = ∅. Although {2, 5} is Aᶜ and {1, 3, 4} is A, neither set is their intersection. Therefore option A is correct.
Frequently asked questions
What is the correct answer to this question?
∅
Why is this the correct answer?
By definition, Aᶜ consists of the elements of U that are not members of A. Thus A and Aᶜ are disjoint sets: they cannot have a common element. This gives the universal identity A ∩ Aᶜ = ∅. Although {2, 5} is Aᶜ and {1, 3, 4} is A, neither set is their intersection. Therefore option A is correct.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Complement of a Set and Its Properties.