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Homework Help: Infinite geometric series problem

  1. Jan 30, 2008 #1
    1. The problem statement, all variables and given/known data

    Consider the following infinite geometric series: 1 + (2x/3) + (2x/3)^2 + (2x/3)^3 + ....

    for what values of x does the series converge?

    2. Relevant equations

    i don't know what converge means, i guessed it was for what vlaues does the geometric series is infinite but i am not sure.

    3. The attempt at a solution
  2. jcsd
  3. Jan 30, 2008 #2


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  4. Jan 30, 2008 #3
    well remember that in order for a geometric series to converge all its terms should be greater than -1 and smaller than 1? do u know what to do now?
  5. Jan 30, 2008 #4
    well, I'm going through this type of math, now there is a formula for geometric series, it is like this: (first term) / (1-r)

    you always want to plug the first term in the top of the equation, in your case it looks like 1.
  6. Jan 30, 2008 #5
    Well, he is looking for something else, he just needs to find the interval of x for which the series converges.
  7. Jan 30, 2008 #6
    thank you so much for that hint it really cleared everything! the web pages kept talking aobut limitations...i remebered now! thanks
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