If B₁ = {x : x ∈ ℝ, x² = 2}, what type of set is B₁?
Answer and explanation
Correct answer: Two-element finite set
Solving x² = 2 over the real numbers gives x = √2 and x = −√2. Therefore, B₁ = {−√2, √2}, which contains exactly two distinct elements. A set with a fixed, countable number of elements is finite. Thus B₁ is a two-element finite set, not an empty or infinite set.
Frequently asked questions
What is the correct answer to this question?
Two-element finite set
Why is this the correct answer?
Solving x² = 2 over the real numbers gives x = √2 and x = −√2. Therefore, B₁ = {−√2, √2}, which contains exactly two distinct elements. A set with a fixed, countable number of elements is finite. Thus B₁ is a two-element finite set, not an empty or infinite set.
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.