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Math Help - limit

  1. #1
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    limit

    what is the limit of (((-1)^n)*n)/(n+1) as n approaches infinity and how do you find it?
    Last edited by hayter221; October 16th 2008 at 04:41 PM.
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  2. #2
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    What does n approach?. 0?. Infinity?. Something else?.
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  3. #3
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    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.
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  4. #4
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    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.
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  5. #5
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    The book we are given says 0.
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