What is the roster form of S = {x : x is an even prime number}?
Answer and explanation
Correct answer: S = {2}
A prime number has exactly two positive factors: 1 and the number itself. The only even prime is 2. Every even number greater than 2 is divisible by both 1 and 2 and has additional factors, so it is composite. Consequently, the set of even prime numbers contains only 2, and its roster form is {2}; option B is correct.
Frequently asked questions
What is the correct answer to this question?
S = {2}
Why is this the correct answer?
A prime number has exactly two positive factors: 1 and the number itself. The only even prime is 2. Every even number greater than 2 is divisible by both 1 and 2 and has additional factors, so it is composite. Consequently, the set of even prime numbers contains only 2, and its roster form is {2}; option B is correct.
Which subject and chapter does this question cover?
This is a Class 9 Mathematics question. Chapter: Common Questions. Topic: General chapter practice.
