ok, the lim of the nth root of (1+3n) Thanks in advance!

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- June 19th 2008, 02:33 PMwinterwyrmexponential limit
ok, the lim of the nth root of (1+3n) Thanks in advance!

- June 19th 2008, 02:37 PMgalactus
What does n approach?.

I assume you mean

If so, let

Then, - June 19th 2008, 07:05 PMMathstud28
- June 19th 2008, 07:30 PMmr fantastic
- June 19th 2008, 10:23 PMMoo
"Qu'est-ce que c'est ?" ^^

If you want to know, you can remember that when dealing with power series and looking for the radius of convergence, you can choose between the ratio or the power test. Both will give the same result (Tongueout)

Now, if you want to*prove*it, that's another matter lol - June 19th 2008, 10:24 PMMathstud28
- June 20th 2008, 04:23 AMmr fantastic
But where is the power series here? Is it meant to be .....?

Quote:

Originally Posted by**Mathstud28**

If then the ratio is wrong for a start.

By the way, regarding "*By the connection between the root and ratio test*" ...... What happens when you apply the ratio test and the nth root test to .....? (Thinking)

(Tongueout) - June 20th 2008, 07:33 AMThePerfectHacker
- June 20th 2008, 08:03 AMMoo
Nah, I was talking about when you want to find the radius of convergence of a series, you can use either the ratio test either the root test to reach the

__same__result.

This is a way to "remember" what mathstud used (Tongueout)

@ TPH : would you mind posting it ? ^^ - June 20th 2008, 10:58 AMmr fantastic
- June 20th 2008, 11:00 AMMathstud28
- June 20th 2008, 05:32 PMmr fantastic
- June 20th 2008, 07:39 PMMathstud28
Are you really going to be that semantical? Well to answer your question, I never said every limit can be done this way, what you provided is a case where the root test and the ratio test differ. What I am talking about is much more specific, it is

By the connection

And cannot have a variable exponent. I will post back later with a more in-depth reasoning. - June 20th 2008, 08:45 PMmr fantastic