Question

find a7 for the geometric series with

Answer 1

\(a_n = a_1 r^{n-1}\)

Answer 2

\(a_7 = a_1 r^{7-1}\)

Answer 3

plugin the given \(a_1 \) and \(r\) values

Answer 4

okay. is that the formula i use

Answer 5

Yes

Answer 6

-24?

Answer 7

try again

Answer 8

where do i put the 86?

Answer 9

\(a_7 = 2 (-2)^{7-1} \)

Answer 10

we dont use 86 for this

Answer 11

128

Answer 12

Yes ! \(a_7 = 128\)

Answer 13

i now have to find a8 do i use the same formula?

Answer 14

they gave me r s8 and a1

Answer 15

yes same formula