If A = {9}, which of the following is P(A)?
Answer and explanation
Correct answer: {∅, {9}}
The set A = {9} has one element. Its only subsets are the empty set ∅ and the set containing its element, {9}. The power set must contain these subsets as its own elements, so P(A) = {∅, {9}}. Option B incorrectly treats 9 as an element directly inside the power set rather than the subset {9}; option A omits the empty subset, and option D mixes element and set notation.
Frequently asked questions
What is the correct answer to this question?
{∅, {9}}
Why is this the correct answer?
The set A = {9} has one element. Its only subsets are the empty set ∅ and the set containing its element, {9}. The power set must contain these subsets as its own elements, so P(A) = {∅, {9}}. Option B incorrectly treats 9 as an element directly inside the power set rather than the subset {9}; option A omits the empty subset, and option D mixes element and set notation.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Power Set and Subsets.
