If U = {1, 2, 3, 4, 5, 6, 7, 8} is the universal set and A = {2, 3, 5, 7}, what is the complement A′ of A?
Answer and explanation
Correct answer: {1, 4, 6, 8}
The governing concept is complement relative to a specified universal set: A′ = U − A. Start with U = {1, 2, 3, 4, 5, 6, 7, 8} and remove every element of A, namely 2, 3, 5, and 7. The elements left are 1, 4, 6, and 8, so A′ = {1, 4, 6, 8}. Option B repeats A rather than finding its complement, and the other options omit valid remaining elements.
Frequently asked questions
What is the correct answer to this question?
{1, 4, 6, 8}
Why is this the correct answer?
The governing concept is complement relative to a specified universal set: A′ = U − A. Start with U = {1, 2, 3, 4, 5, 6, 7, 8} and remove every element of A, namely 2, 3, 5, and 7. The elements left are 1, 4, 6, and 8, so A′ = {1, 4, 6, 8}. Option B repeats A rather than finding its complement, and the other options omit valid remaining elements.
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.
