If A = {x : x ∈ N, 1 ≤ x ≤ 12}, B = {2, 4, 6, 8, 10, 12}, and C = {3, 6, 9, 12}, what is A \ (B ∪ C)?
Answer and explanation
Correct answer: {1, 5, 7, 11}
A is the set of natural numbers from 1 through 12. First form the union B ∪ C, which contains every element appearing in either set: {2, 3, 4, 6, 8, 9, 10, 12}. Set difference A \ (B ∪ C) keeps elements of A that are absent from this union. Checking 1 through 12 leaves 1, 5, 7, and 11. Therefore option A is correct.
Frequently asked questions
What is the correct answer to this question?
{1, 5, 7, 11}
Why is this the correct answer?
A is the set of natural numbers from 1 through 12. First form the union B ∪ C, which contains every element appearing in either set: {2, 3, 4, 6, 8, 9, 10, 12}. Set difference A \ (B ∪ C) keeps elements of A that are absent from this union. Checking 1 through 12 leaves 1, 5, 7, and 11. Therefore option A is correct.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Operations on Sets (Union, Intersection, Difference).
