Question

1. What is the sum of the geometric sequence 8, –16, 32 … if there are 15 terms?

Answer 1

how do i do this?

Answer 2

anyone?

Answer 3

use the formula

Sum = a r^n - 1
--------
r - 2

where a = first term, n = number of terms and r = common ratio

common ration = -16 / 8 = -2

Answer 4

how did u know the common ratio

Answer 5

8-2^15-1
---------
-2-2 ?

Answer 6

(8 * -2^15) - 1
---------
-2-2

Answer 7

terms in a GP are of the form a,ar,ar^2,ar^3

so r = common ratio = ar /a
in the above a = 8 and ar = -16

Answer 8

sum =[ 8* -32768 - 1] / -4

Answer 9

65536.25
\
- sum of GP with a common ratio integer >|1| gets bigger pretty quickly

Answer 10

need any more help?