MCQ
$\lim _{n \rightarrow \infty}\left\{\frac{2}{3}+\left(\frac{2}{3}\right)^2+\left(\frac{2}{3}\right)^3+\ldots+\left(\frac{2}{3}\right)^n\right\}$ is equal to
  • A
    $\frac{1}{2}$
  • 2
  • C
    1
  • D
    3

Answer

Correct option: B.
2
(B)
$\lim _{n \rightarrow \infty}\left[\frac{2}{3}+\left(\frac{2}{3}\right)^2+\left(\frac{2}{3}\right)^3+\ldots+\left(\frac{2}{3}\right)^n\right]$
$=\lim _{n \rightarrow \infty} \frac{\frac{2}{3}\left(1-\left(\frac{2}{3}\right)^n\right)}{1-\frac{2}{3}}=\lim _{n \rightarrow \infty} 2\left[1-\left(\frac{2}{3}\right)^n\right]$
$=2(1-0)=2^3$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free