If U = {1, 2, 3, 4, 5, 6, 7, 8, 9} and A = {2, 4, 6, 8}, what is the complement A′ of A with respect to U?
Answer and explanation
Correct answer: {1, 3, 5, 7, 9}
The governing definition is A′ = U − A: the complement contains precisely those elements of U that are absent from A. Removing 2, 4, 6, and 8 from U = {1, 2, 3, 4, 5, 6, 7, 8, 9} leaves the odd elements {1, 3, 5, 7, 9}. Hence option A is correct. Option B is A itself, option C is the whole universal set, and option D would apply only if A equalled U.
Frequently asked questions
What is the correct answer to this question?
{1, 3, 5, 7, 9}
Why is this the correct answer?
The governing definition is A′ = U − A: the complement contains precisely those elements of U that are absent from A. Removing 2, 4, 6, and 8 from U = {1, 2, 3, 4, 5, 6, 7, 8, 9} leaves the odd elements {1, 3, 5, 7, 9}. Hence option A is correct. Option B is A itself, option C is the whole universal set, and option D would apply only if A equalled U.
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.
