JEE Mains · Maths · STD 11 - 1. set theory
If \(X = \{ {4^n} - 3n - 1:n \in N\} \) and \(Y = \{ 9(n - 1):n \in N\} ,\) then \(X \cup Y\) = . . . . .
- A \(X\)
- B \(Y\)
- C \(N\)
- D None of these
Answer & Solution
Correct Answer
(B) \(Y\)
Step-by-step Solution
Detailed explanation
\( x=\left\{4^{n}-3 n-1\right\} \) \(=\{0,9,54, \ldots\} \) \( Y =\{9(n-1)\} \) \(=\{0,9,18,27, \ldots\} \) \( \therefore X U Y=Y \)
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