For the set A = {x ∈ R : x² = 4}, which statement is correct?
Answer and explanation
Correct answer: A = {−2, 2}
To find the members of A, solve the equation x² = 4 over the real numbers. Taking square roots gives x = 2 or x = −2. Therefore, both values belong to the solution set, so A = {−2, 2}. The braces indicate a set containing two separate numbers; they do not represent every number in an interval. Hence option B is correct.
Frequently asked questions
What is the correct answer to this question?
A = {−2, 2}
Why is this the correct answer?
To find the members of A, solve the equation x² = 4 over the real numbers. Taking square roots gives x = 2 or x = −2. Therefore, both values belong to the solution set, so A = {−2, 2}. The braces indicate a set containing two separate numbers; they do not represent every number in an interval. Hence option B is correct.
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.
