JEE Previous Year Question
Let S = {1, 2, 3, 4}. The total number of unordered pairs of disjoint subsets of S is equal to
Topic: JEE PYQ
Answer: D. Full step-by-step solution below.
- A25
- B34
- C42
- D41
Correct answer: D
Solution
(d)S = {1, 2, 3, 4}Each element can be put in 3 ways either in subsets or we don’t put in any subset.
So total number of unordered pairs = + 1 = 41. [Both subsets can be empty also]
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