What is the next step for determining convergence or divergence of this series?

In summary, the series \displaystyle \sum^{∞}_{n=1} (-1)^n \frac{6n^8 + 3}{3n^5 + 3} either absolutely converges, conditionally converges, or diverges. The alternating series test cannot be used since the function is increasing, not decreasing. However, the series can be determined to diverge by using the divergence test since its terms do not approach zero.
  • #1
whatlifeforme
219
0

Homework Statement


determine either absolute convergence, conditional convergence, or divergence for the series.

Homework Equations


[itex]\displaystyle \sum^{∞}_{n=1} (-1)^n \frac{6n^8 + 3}{3n^5 + 3} [/itex]

The Attempt at a Solution


I cannot use the alternating series test since the function is increasing not decreasing.What should i do next?
 
Physics news on Phys.org
  • #2
whatlifeforme said:

Homework Statement


determine either absolute convergence, conditional convergence, or divergence for the series.


Homework Equations


[itex]\displaystyle \sum^{∞}_{n=1} (-1)^n \frac{6n^8 + 3}{3n^5 + 3} [/itex]


The Attempt at a Solution


I cannot use the alternating series test since the function is increasing not decreasing.What should i do next?
Since the sequence (apart from the (-1)n factor) is increasing, doesn't that give you a hint as to what the series is doing? It might help to write a few terms in the series.
 
  • #3
can i use the divergence test?
 
  • #4
Yep, it diverges since its terms do not approach zero.
 
  • #5
HS-Scientist said:
Yep, it diverges since its terms do not approach zero.

thanks.
 

Related to What is the next step for determining convergence or divergence of this series?

What is the Alternating Series Test?

The Alternating Series Test is a mathematical test used to determine the convergence or divergence of an infinite series. It specifically applies to alternating series, where the signs of the terms alternate between positive and negative.

How does the Alternating Series Test work?

The Alternating Series Test states that if a series alternates in sign and each term is smaller than the previous term, then the series will converge. This means that the terms must eventually approach zero as the series continues.

When does the Alternating Series Test fail?

The Alternating Series Test may fail in two cases: when the series does not alternate in sign, or when the terms do not decrease in magnitude. In these cases, the test cannot be used to determine the convergence or divergence of the series.

Are there any exceptions to the Alternating Series Test?

Yes, there are a few exceptions to the Alternating Series Test. For example, if the series is a geometric series or a telescoping series, the test may not be applicable. In these cases, other tests must be used to determine convergence or divergence.

Why is the Alternating Series Test important?

The Alternating Series Test is important because it provides a simple and efficient way to determine the convergence or divergence of an infinite series. It is also a useful tool in many other mathematical and scientific applications, such as in the analysis of alternating currents in electrical engineering.

Similar threads

  • Calculus and Beyond Homework Help
Replies
2
Views
218
  • Calculus and Beyond Homework Help
Replies
14
Views
1K
  • Calculus and Beyond Homework Help
Replies
1
Views
291
  • Calculus and Beyond Homework Help
Replies
4
Views
1K
  • Calculus and Beyond Homework Help
Replies
2
Views
722
  • Calculus and Beyond Homework Help
Replies
5
Views
1K
  • Calculus and Beyond Homework Help
Replies
7
Views
973
  • Calculus and Beyond Homework Help
Replies
29
Views
1K
  • Calculus and Beyond Homework Help
Replies
3
Views
432
  • Calculus and Beyond Homework Help
Replies
1
Views
789
Back
Top