- #1

- 139

- 0

Hello, I am trying to determine if this series converges or diverges. I have tried comparison test and d'Alembert's test but I was not successful

Can anyone suggest me a test learned in Calculus 2 that will work?

Thank you

You are using an out of date browser. It may not display this or other websites correctly.

You should upgrade or use an alternative browser.

You should upgrade or use an alternative browser.

- Thread starter fishingspree2
- Start date

- #1

- 139

- 0

Hello, I am trying to determine if this series converges or diverges. I have tried comparison test and d'Alembert's test but I was not successful

Can anyone suggest me a test learned in Calculus 2 that will work?

Thank you

- #2

- 392

- 0

Break it into a sum of two series?

- #3

Cyosis

Homework Helper

- 1,495

- 0

[tex]

\lim_{n \to \infty}\sqrt[n]{|a_n|}<1

[/tex]

It converges absolutely if the limit is smaller than 1.

- #4

- 139

- 0

[tex]\sum_{k=1}^{\infty}\frac{\left|\cos k \right|}{k^{3}}[/tex]

It looks like a riemann series but I don't really know how to deal with trigonometric functions in series yet. What to do? Can anyone explain me?

Thank you

- #5

- 614

- 0

What values can |cos k| take? Perhaps consider a p-series

Share: