Question

geometric sequences

Answer 1

Find an explicit rule for the nth term of a geometric sequence where the second and fifth terms are -36 and 2304, respectively.

Answer 2

do you know the n'th term formula ?

Answer 3

the one you told me previously :D

Answer 4

lol. that was arithmetic?
anyways its this
\(\large a_n = a_1 r^{n-1}\)
plug in n =2 here
what u get ?

Answer 5

wait a1r^2-1=a_1r

Answer 6

you mean \(a_2 = a_1r^{2-1}\)
?

Answer 7

yeah ^.^ i just didnt put a_2

Answer 8

so then its a_2=a_1r because 1 as an exponent dosent do anything

Answer 9

a2 = 2nd term = -36
\(-36 = ar\)
got this ?

Answer 10

yeah cuz it already said that\

Answer 11

now plug in n=5 in the n'th term formula
what u get ?

Answer 12

because you have 5th term