If A = {x ∈ ℝ : −3 ≤ x ≤ 2} and B = {x ∈ ℝ : −1 < x < 4}, what is A − B?
Answer and explanation
Correct answer: [−3, −1]
The difference A − B consists of elements that are in A but not in B. Set A is the interval [−3, 2], while B contains all numbers strictly between −1 and 4. Thus, every point from just greater than −1 through 2 is removed from A. The point −1 remains because −1 belongs to A but is excluded from B. Therefore, A − B = [−3, −1].
Frequently asked questions
What is the correct answer to this question?
[−3, −1]
Why is this the correct answer?
The difference A − B consists of elements that are in A but not in B. Set A is the interval [−3, 2], while B contains all numbers strictly between −1 and 4. Thus, every point from just greater than −1 through 2 is removed from A. The point −1 remains because −1 belongs to A but is excluded from B. Therefore, A − B = [−3, −1].
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Operations on Sets (Union, Intersection, Difference).
