Question

I seen many problems like these here
http://openstudy.com/study#/updates/5140bf27e4b0f08cbdc91cc0

put what if you where given third term is -96 and 6th term is -6144.

its different cuzz you are not giving a as usual.

how would you go about solving it? I am just thinking. You'd have to do some kind of system of equations right?

Answer 1

Correct. You would want to find d and a1 by knowing that a3=-96 , and thus n=3, and a6=-6144 and thus n=6.

Answer 2

you would divide n'th term formulas for 3rd and 6th term
this will give you common ratio=r
then using any of the n'th term formula you can get 'a' also

Answer 3

a3 = a1 r^2
a6 = a1 r^5
if you divide these 2, you get r^3 and hence 'r'

Answer 4

then using a3 = a1 r^2
you can get a1 also

Answer 5

oops, I did t again. I used arithmetic when I should have used geometric. Skip my posts, and go with hartnn's!

Answer 6

monster truck?