Question

the some of first 8 term of the sequence 3,6,12,24..........is?

Answer 1

it is in GP.. FOR EXAMPLE . 6÷3=12÷6=24÷12.... SO ON . SO IT IS IN GP. PUT GP SUMMATION FORMULA . AND MADE IT

Answer 2

Here,
a = 3
r = 6/3 =2 (which is greater than 1)
n = 8

Using,
$sn = a( {r}^{n} - 1) \div (r - 1)$
We get sn = 3(2^8 - 1) / (2-1)
= 3(256-1) /1
= 3(255)
= 765