Question

the sum of the first eight terms of the series 3 -12 + 48 - 192 + ... is

Answer 1

observe that it is a GP of common ratio=-4

Answer 2

\[\frac{ 3(1-(-4)^n) }{ 1-(-4) }\]

Answer 3

i have generalised the summation for n terms

Answer 4

put n=8 for summation till 8 terms

Answer 5

is it -39321

Answer 6

@cody_123

Answer 7

i got 39322.2 :(

Answer 8

hw did u get that..., I got -39321 @cê31

Answer 9

ohhhhhhhhh, I didn't see the 2 negatives

Answer 10

u just had to apply the correct formula and rest was calculation

Answer 11

thank u :))))))) I think I got the right answer now. -39321