Question

Write a formula for the general term (the nth term) of the geometric sequence.

Answer 1

how do you get from the first to the second term?

Answer 2

wow is that ugly!
look at those little minus signs
i almost missed them

Answer 3

I dont know where to begin.

Answer 4

what do you multiply \(\frac{1}{2}\) by to get \(-\frac{1}{10}\) ?

Answer 5

-1/5

Answer 6

yeah... they're not very clear.

Answer 7

ikr

Answer 8

yeah you are right, it is \(-\frac{1}{5}\)

Answer 9

so each term is the previous term times \(-\frac{1}{5}\)

Answer 10

\(a_n\) is the \(n\)th term
the term before that, i.e. the previous term, is \(a_{n-1}\)

Answer 11

therefore you could say \(a_n=-\frac{1}{5}a_{n-1}\)

Answer 12

as usual, the answer is C
it is always C

Answer 13

Thank you very much.

Answer 14

yw

Answer 15

to me, it is \[a_n = \frac{1}{2}(-\frac{1}{5})^{n-1}\]