What is A = {x ∈ ℤ : x is even and x² = 2x}?
Answer and explanation
Correct answer: A = {0, 2}
Solve the equation x² = 2x by bringing all terms to one side: x² − 2x = 0, so x(x − 2) = 0. Hence x = 0 or x = 2. Both values are integers, and both are even because each is divisible by 2; zero is also an even integer since 0 = 2 × 0. Therefore, the required set is A = {0, 2}.
Frequently asked questions
What is the correct answer to this question?
A = {0, 2}
Why is this the correct answer?
Solve the equation x² = 2x by bringing all terms to one side: x² − 2x = 0, so x(x − 2) = 0. Hence x = 0 or x = 2. Both values are integers, and both are even because each is divisible by 2; zero is also an even integer since 0 = 2 × 0. Therefore, the required set is A = {0, 2}.
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.