If A = {x ∈ ℕ : x² ≤ 49}, which set is A equal to?
Answer and explanation
Correct answer: {1, 2, 3, 4, 5, 6, 7}
Since x belongs to ℕ, take the positive natural numbers under the convention used in the options: 1, 2, 3, and so on. The inequality x² ≤ 49 gives x ≤ 7 for natural numbers. Thus the possible values are 1 through 7, so A = {1, 2, 3, 4, 5, 6, 7}. Negative integers are excluded because the domain is ℕ.
Frequently asked questions
What is the correct answer to this question?
{1, 2, 3, 4, 5, 6, 7}
Why is this the correct answer?
Since x belongs to ℕ, take the positive natural numbers under the convention used in the options: 1, 2, 3, and so on. The inequality x² ≤ 49 gives x ≤ 7 for natural numbers. Thus the possible values are 1 through 7, so A = {1, 2, 3, 4, 5, 6, 7}. Negative integers are excluded because the domain is ℕ.
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.
