SOLUTION: Given the following sequence in geometric, find the common ratio and find the 10 th term: {{{c[n]=(-3/2)^(n-3)}}} please i need help please urgent!!!!!!!!! i have exam on t

Algebra ->  Sequences-and-series -> SOLUTION: Given the following sequence in geometric, find the common ratio and find the 10 th term: {{{c[n]=(-3/2)^(n-3)}}} please i need help please urgent!!!!!!!!! i have exam on t      Log On


   

Question 195833: Given the following sequence in geometric, find the common ratio and find the 10 th term:
c%5Bn%5D=%28-3%2F2%29%5E%28n-3%29
please i need help please urgent!!!!!!!!!
i have exam on this question please.....
Found 3 solutions by user_dude2008, RAY100, Edwin McCravy:
Answer by user_dude2008(1862) About Me  (Show Source):
You can put this solution on YOUR website!



common ratio:


Tenth term:

Answer by RAY100(1637) About Me  (Show Source):
You can put this solution on YOUR website!
C(n) = (-3/2)^n-3
.
std form is ,,,,a(n) = a(1) r^(n-1)
,
common ratio is (-3/2) or -1.5
,
10 th term is , C(10) = (-3/2) ^ (10-3) = (-3/2)^7 = -17.09

Answer by Edwin McCravy(20060) About Me  (Show Source):
You can put this solution on YOUR website!
c%5Bn%5D=%28-3%2F2%29%5E%28n-3%29

Let's find the first two terms:

Let n=1

c%5B1%5D=%28-3%2F2%29%5E%281-3%29=%28-3%2F2%29%5E%28-2%29=%28-2%2F3%29%5E2=4%2F9

c%5B2%5D=%28-3%2F2%29%5E%282-3%29=%28-3%2F2%29%5E%28-1%29=%28-2%2F3%29%5E1=-2%2F3


The common ratio is found by dividing any term by
the preceding term, so we'll divide c%5B2%5D%2Fc%5B1%5D=%28-2%2F3%29%2F%284%2F9%29=%28-2%2F3%29%289%2F4%29=-3%2F2

So the ommon ratio r=-3%2F2

The 10th term is

c%5B10%5D=%28-3%2F2%29%5E%2810-3%29=%28-3%2F2%29%5E%287%29=-2187%2F128

Edwin