SOLUTION: Can someone show me how to work these? Find the 5th term for each: 1: A1=20, An=1/2A(n-1)+2 2: An=8n-5 3: A1=1/2, An=2A(n-1) I came up with 35 for #2, but I'm not even s

Algebra.Com
Question 429511: Can someone show me how to work these?
Find the 5th term for each:
1: A1=20, An=1/2A(n-1)+2
2: An=8n-5
3: A1=1/2, An=2A(n-1)
I came up with 35 for #2, but I'm not even sure that's right. These are confusing me!
Thanks!

Answer by vleith(2983)   (Show Source): You can put this solution on YOUR website!
you are correct for number 2. Let's do problem 1 and then you can use the same process to do 3.
You are given
and told
So now find
Plug in 2 for n in the given forumula


Now you see this formula contains which you know is 20. So subsitute 20 and solve



Now you have . So now solve for when n=3

you know because you just solved for it above. Plug 12 in for and solve for



Keep doing this process for n = 4 and then again for n=5.


Use the same process for problem 3

RELATED QUESTIONS

My problem is to find the indicated term for the geometric series described : Sn=33... (answered by Theo)
Can someone please help me? 1. Find the sum of each arithmetic series. Part I: -15 + -3 (answered by josgarithmetic)
to find the first 3 terms of the Recursively defined sequence: a1=5 , an=2a n-1 for... (answered by Fombitz,jim_thompson5910)
What are the first five terms 50th term of this sequence? An=2a n-1 + 5 and... (answered by ikleyn)
what is the first five terms and 50th term of this sequence. An=2a n-1 + 5 and... (answered by greenestamps)
what is the first five terms and 50th term of this sequence. An=2a n-1 + 5 and... (answered by ikleyn,greenestamps,Edwin McCravy)
Find the fifth term of the following sequence: a1 = 2; an = n^2 + an-1 (answered by ikleyn)
I have to do two problems dealing with arithmetic and geometric sequence. I am taking... (answered by stanbon)
I'm so confused. Can someone pretty please help with these? For the following sequences... (answered by Edwin McCravy)