ExamBro
ExamBro
WBJEE · Maths · Sequences and Series

The value of \(\lim _{n \rightarrow \infty}\left[\left(\frac{1}{2 \cdot 3}+\frac{1}{2^2 \cdot 3}\right)+\left(\frac{1}{2^2 \cdot 3^2}+\frac{1}{2^3 \cdot 3^2}\right)+\ldots+\left(\frac{1}{2^n \cdot 3^n}+\frac{1}{2^{n+1} \cdot 3^n}\right)\right]\) is

  1. A \(\frac{3}{8}\)
  2. B \(\frac{3}{10}\)
  3. C \(\frac{3}{14}\)
  4. D \(\frac{3}{16}\)
Verified Solution

Answer & Solution

Correct Answer

(B) \(\frac{3}{10}\)

Step-by-step Solution

Detailed explanation

\begin{aligned} \text{Hint : } & \lim _{n \rightarrow \infty} \sum_{x=1}^n\left(\frac{1}{2^x \times 3^x}+\frac{1}{2^{x+1} \times 3^x}\right) \\ & =\lim _{n \rightarrow \infty} \sum_{x=1}^n \frac{1}{6^x}\left(1+\frac{1}{2}\right) \\ & =\frac{3}{2} \times \underbrace{\lim _{n…