Question

find the sum to the required number of terms for the geometric series
2-1+1/2 -1/4+... to 6 terms

just want to check if i got the answer right. using the formula s=b1*(1-q^n)/(1-q) , i got 21/16
is that right?

Answer 1

\[1 + 1/2 - 1/4 + 1/8 - 1/16 \\ = 1+1/4 + 1/8 - 1/16\\ = 1 + 3/8 - 1/16\\ = 1 + 5/8\]

Answer 2

So you're correct!

Answer 3

When I don't have a paper, I just add those up. Haha

Answer 4

but 1+5/8 is 13/8

Answer 5

13/8 = 1.625
and 21/16=1.31

Answer 6

Where is the lamp @AravindG

Answer 7

grr, I meant \(1 + \dfrac{5}{16}\)

Answer 8

ohh lol ok that makes sense

Answer 9

grr nice peculiure sound you make

Answer 10

@ParthKohli it was for you baby