If A = {∅, {∅}}, what is n(P(A))?
Answer and explanation
Correct answer: 4
The set A has two distinct elements: the empty set ∅ and the singleton set {∅}. Although one is formed from the other, they are not equal; ∅ has no elements, whereas {∅} has one element, namely ∅. Therefore |A| = 2, and the power set has 2² = 4 elements: ∅, {∅}, {{∅}}, and {∅,{∅}}. Option C is correct.
Frequently asked questions
What is the correct answer to this question?
4
Why is this the correct answer?
The set A has two distinct elements: the empty set ∅ and the singleton set {∅}. Although one is formed from the other, they are not equal; ∅ has no elements, whereas {∅} has one element, namely ∅. Therefore |A| = 2, and the power set has 2² = 4 elements: ∅, {∅}, {{∅}}, and {∅,{∅}}. Option C is correct.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Power Set and Subsets.