Manipal MET2018MathematicsSequences and Series
The sum of infinite terms of the geometric progression 2 +1 2 -1 , 1 2- 2 , 1 2 , is
Options
- A2 ( 2 +1)^2
- B5 2
- C( 2 +1)^2
- D3 2 + 5
Correct answer
A. 2 ( 2 +1)^2
Step-by-step solution
In the given series a= 2 +1 2 -1 and r= 1 2+ 2 = 2- 2 2 S_ = a 1-r = 2 +1 2 -1 1- 2- 2 2 aligned & = 2 +1 2 -1 2 2 = 2 ( 2 +1) 2 -1 2 +1 2 +1 & = 2 ( 2 +1)^2 aligned