- #1

mr_coffee

- 1,629

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hello everyone, I'm trying to figure out this geometric progession and I'm checking it with my calculator and I'm definatley not getting what they are getting:

I'm trying to find the term after the last term, I found the ratio which is 3/2, now I must multiply that ratio by the last term which is:

So i'd have:

(3/2)*(2^3)*3^(n-3)

The calculator spits out:

(4/9)*3^n

I did this problem before and I got that I don't know where my brain is, but now I'm getting:

4*3^(n-2);

Becuase the 2 will cancel out the 8, and leave you 4, and 3 x 3^(n-3) is like 3^(n-3+1) = 3^(n-2)

What am I missing?

Here is the geometric progression and below is my work, once I apply the formula its simple aglebra and adding of exponents but I keep screwing it up.

http://suprfile.com/src/1/4ds5zep/lastscan.jpg

Thanks!

I'm trying to find the term after the last term, I found the ratio which is 3/2, now I must multiply that ratio by the last term which is:

**(2^3)*3^(n-3)**So i'd have:

(3/2)*(2^3)*3^(n-3)

The calculator spits out:

(4/9)*3^n

I did this problem before and I got that I don't know where my brain is, but now I'm getting:

4*3^(n-2);

Becuase the 2 will cancel out the 8, and leave you 4, and 3 x 3^(n-3) is like 3^(n-3+1) = 3^(n-2)

What am I missing?

Here is the geometric progression and below is my work, once I apply the formula its simple aglebra and adding of exponents but I keep screwing it up.

http://suprfile.com/src/1/4ds5zep/lastscan.jpg

Thanks!

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