If A = {x ∈ ℤ : |2x − 1| < 4} and B = {−1, 0, 1, 2}, which conclusion is correct?
Answer and explanation
Correct answer: A = B
We solve the absolute-value inequality first: |2x − 1| < 4 implies −4 < 2x − 1 < 4. Adding 1 and dividing by 2 gives −3/2 < x < 5/2. Since x must be an integer, the possible values are −1, 0, 1, and 2. Therefore A = {−1, 0, 1, 2}, which is exactly the set B. Hence the correct conclusion is A = B.
Frequently asked questions
What is the correct answer to this question?
A = B
Why is this the correct answer?
We solve the absolute-value inequality first: |2x − 1| < 4 implies −4 < 2x − 1 < 4. Adding 1 and dividing by 2 gives −3/2 < x < 5/2. Since x must be an integer, the possible values are −1, 0, 1, and 2. Therefore A = {−1, 0, 1, 2}, which is exactly the set B. Hence the correct conclusion is A = B.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: The Empty Set, Finite and Infinite Sets, Equal Sets.