If A = {1, 2}, what is the total number of subsets of A?
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Answer and explanation
Correct answer: 4
A set containing n distinct elements has 2ⁿ subsets, because each element has two independent choices: it may either be included in a subset or excluded from it. Here n = 2, so the number of subsets is 2² = 4. They are ∅, {1}, {2}, and {1, 2}. Both the empty set and the original set itself must be counted.
Frequently asked questions
What is the correct answer to this question?
4
Why is this the correct answer?
A set containing n distinct elements has 2ⁿ subsets, because each element has two independent choices: it may either be included in a subset or excluded from it. Here n = 2, so the number of subsets is 2² = 4. They are ∅, {1}, {2}, and {1, 2}. Both the empty set and the original set itself must be counted.
Which subject and chapter does this question cover?
This is a Class 10 Mathematics question. Chapter: Sets. Topic: Power Set and Subsets.
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