Determine whether the sequence converges or diverges. If it converges, give the limit.
108, -18, 3, -1/2

Question

Determine whether the sequence converges or diverges. If it converges, give the limit.
108, -18, 3, -1/2

anonymous · Answer

it explodes

jim_thompson5910 · Answer

what type of sequence is this? any ideas?

anonymous · Answer

arithmetic?

jim_thompson5910 · Answer

no it's not arithmetic

anonymous · Answer

then geometric.

anonymous · Answer

you sere its not power

jim_thompson5910 · Answer

subtract any two consecutive terms and you'll find the differences aren't the same

so there's no common difference

jim_thompson5910 · Answer

yes it's a geometric sequence

jim_thompson5910 · Answer

first term is a = 108

common ratio is  r= -18/108 = -1/6

anonymous · Answer

I see, is that a way to always prove its not arithmetic?

anonymous · Answer

so we're going to use a formula for this right?

anonymous · Answer

this jim is helping so good

anonymous · Answer

hey jim you know anything about transport phenomena

anonymous · Answer

What do i do with the "a" and "r". Is there a formula?

anonymous · Answer

jimbo you know anything about dimensional analysis.

anonymous · Answer

Type geometric series into google and it will give you an easy reference

anonymous · Answer

Try Pauls Online Math notes but this kinda stuff should be in your book.

jim_thompson5910 · Answer

sry the site is going slow for me

but you then use the formula

S = a/(1 - r)

to find out what it converges to