limit

hayter221 · #1 $Old$ October 16th, 2008, 06:00 PM

what is the limit of (((-1)^n)*n)/(n+1) as n approaches infinity and how do you find it?

galactus · #2 $Old$ October 16th, 2008, 06:23 PM

What does n approach?. 0?. Infinity?. Something else?.

hayter221 · #3 $Old$ October 16th, 2008, 06:40 PM

oh yea its infinity, I have to prove the answer using limi theorems, but I am lost because I do not know how to find the limit or break it up.

galactus · #4 $Old$ October 16th, 2008, 06:55 PM

I think it is undefined because of the (-1)^n. You could rewrite

$(-1)^{n}\cdot n=n\cdot cos(n{\pi})+n\cdot i\cdot sin(n{\pi})$

You could try L'Hopital's rule.

Frankly, we could say it is -1....1

Thus undefined. Perhaps someone else has another idea.

hayter221 · #5 $Old$ October 16th, 2008, 07:43 PM

The book we are given says 0.