Yahoo Answers is shutting down on May 4th, 2021 (Eastern Time) and beginning April 20th, 2021 (Eastern Time) the Yahoo Answers website will be in read-only mode. There will be no changes to other Yahoo properties or services, or your Yahoo account. You can find more information about the Yahoo Answers shutdown and how to download your data on this help page.
Trending News
geometric sequence?
Solve the nth term for the following progression which only has positive real numbers and has u_2=8 and u_6=128
3 Answers
- Keith ALv 65 years ago
u_2 = 8, = a * r^1
u_6 = 128, = a * r^5
So 128 / 8 = (a * r^5) / (a * r)
I.e., 16 = r^4
So r = 2 (positive terms only)
So a = 8 / 2 = 4
(Determine (sic) the nth term: )
u_n = a * r^(n - 1)
= 4 * 2^(n - 1)
= 2^(n + 1)
- Jeff AaronLv 75 years ago
It could be any one of these geometric sequences:
The first term is -4 and the common ratio is -2
The first term is 4 and the common ratio is 2
The first term is -4i and the common ratio is 2i
The first term is 4i and the common ratio is -2i
- ?Lv 75 years ago
u_2 = 8, u_6 = 128
d = (128 - 8)/4 = 30
u_1 = 8 - 30 = -22
u_n = -22 + 30(n - 1)
u_n = 30n - 52
