Sequence And Series Question 632
Question: The sum to infinity of the progression $ 9-3+1-\frac{1}{3}+….. $ is
[Karnataka CET 2005]
Options:
A) 9
B) 9/2
C) 27/4
D) 15/2
Show Answer
Answer:
Correct Answer: C
Solution:
Infinite series $ 9-3+1-\frac{1}{3}……\infty $ is a G.P. with $ a=9,r=\frac{-1}{3} $ \ $ {S_{\infty }}=\frac{a}{1-r}=\frac{9}{1+( \frac{1}{3} )}=\frac{9\times 3}{4}=\frac{27}{4} $ .
BETA
