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Homework Help: Proof question

  1. Jan 26, 2008 #1
    1. The problem statement, all variables and given/known data

    Prove by an example that the sum or product of two non convergent sequences can be convergent

    2. Relevant equations

    There are none, they can be any sequences I guess

    3. The attempt at a solution

    I've tried alot of possibilities. My first guess would be a series times it reciprocal, but that just gives every term to be one, so, I dont know if thats really a good example. I also tried adding a sequence to i'ts negative sequence, but, that o course gives zero for every term. I dont think thats what he's looking for either. I also tried adding a function that goes to infinity to a function that goes to negative function, but I found that one function always outweighs the other, Any help would be appreciated.
    1. The problem statement, all variables and given/known data



    2. Relevant equations



    3. The attempt at a solution
     
  2. jcsd
  3. Jan 26, 2008 #2
    well i'm sure you've shown that a_n = (-1)^n doesn't converge, now what's a_na_n?
     
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