If A = {x : x ∈ ℤ, x² − 4x = 0}, which is the correct roster form of A?
Answer and explanation
Correct answer: A = {0, 4}
To find the elements, solve the condition x² − 4x = 0. Factoring gives x(x − 4) = 0, so either x = 0 or x = 4. Both solutions are integers and therefore satisfy the domain restriction x ∈ ℤ. No other value makes the equation true. Thus the roster form is A = {0, 4}, so option A is correct.
Frequently asked questions
What is the correct answer to this question?
A = {0, 4}
Why is this the correct answer?
To find the elements, solve the condition x² − 4x = 0. Factoring gives x(x − 4) = 0, so either x = 0 or x = 4. Both solutions are integers and therefore satisfy the domain restriction x ∈ ℤ. No other value makes the equation true. Thus the roster form is A = {0, 4}, so option A is correct.
Which subject and chapter does this question cover?
This is a Class 12 Mathematics question. Chapter: Sets.
Student feedback
Was this question useful?
👍 0 Helpful 👎 0 Not helpful
Yes 0% No 0%
0 responsesStudent Reviews
No published reviews yet.
