How Do I Find the Nth Term and Sum of These Series?

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Homework Help Overview

The discussion revolves around finding the nth term and the sum of two series. The first series involves the terms 1/2, 1/3, 2/9, 4/27, 8/81, and 16/243, while the second series is an alternating series represented by \(\Sigma (-1)^{n-1}/(5n+1)\). Participants express confusion and seek clarification on both problems.

Discussion Character

  • Exploratory, Conceptual clarification, Problem interpretation

Approaches and Questions Raised

  • Participants discuss expressing the first series in terms of powers of 2 and 3. There is uncertainty about the second series, with requests for clarification on its structure and summation.

Discussion Status

Some participants have made progress in identifying the nth term of the first series, while others continue to struggle with the second series. Clarifications are being sought regarding the notation and structure of the second series, indicating a lack of consensus on its interpretation.

Contextual Notes

Participants mention that the second series starts at n=1 and express difficulty in understanding the notation used for the summation. There is a sense of urgency in seeking help, particularly for the second problem.

wccrooks
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Ok i have a few here that i have no idea what to do
b]1. Homework Statement [/b]

Find the nth term in the series
1/2, 1/3, 2/9, 4/27, 8/81, 16/243

also

[tex]\Sigma[/tex] (-1)^n-1/ 5n+1
find the sum
Urgent help neededdd ahha.. Thanks
 
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For the first: Try to express the terms as a product of powers of 2 and 3. Biggest hint: 1/2=2^(-1)*3^0. For the second, could you clarify the sum?
 
So the 1/2 is just clarifying an alternating series? I am completely lost on that problem. for the second i don't know what you mean either haha... all i know right now is it is an alternating problem... I have been trying to do these for like 3 hours to no success haha..



edit---
Well thanks for the first part i figured out the nth term. I am just super slow haha... The second problem however the only info i have oin it is its starts at n=1 the the (-1)^n-1/5n+1 then it asks me to find the sum I am pretty sure that all i have
 
Last edited:
Like I said, clarify the sum. Use parentheses and such because I can't make any sense out of what you wrote.
 


The sequence looks like 2^(n-1) * 3^n starting from 0
 
ok starting at n=1 ((-1)^n-1)/(5n+1) so as far as i got is the (-1)^n-1 is pulled out as alternating leaving 1/(5n+1) and they want the sum of that
 

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