1. Limited time only! Sign up for a free 30min personal tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Homework Help: Infinite Series: Find Function

  1. Nov 25, 2005 #1
    Hello all!
    I have the following infinite series:


    How would I find a function, f(x), of this series?

    I know the series converges for [tex]\vert x \vert > 1[/tex]

    I think the function is: [tex]f(x) = \frac{10}{x-1}[/tex]

    but I'm not sure how to get it.

  2. jcsd
  3. Nov 25, 2005 #2
    why the x-1 in the denominator?
    maybe this

    [tex]f_{n}(x) = \frac{10}{x^n}[/tex]



    will be what you started with, but I may be worng and/or missing something though.
    Last edited: Nov 25, 2005
  4. Nov 25, 2005 #3

    Physics Monkey

    User Avatar
    Science Advisor
    Homework Helper

    Hint: factor out a 10/x and see if the remaining series looks familiar to you.
  5. Nov 25, 2005 #4
    Ugggh! I'm so blind sometimes...must be all the turkey I ate yesterday. I see the geometric series.

    Thanks, PM.

Share this great discussion with others via Reddit, Google+, Twitter, or Facebook