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 proof

  1. Oct 24, 2005 #1
    I'm working on this problem:
    If {s_n} is a nondecreasing sequence and s_n>=0, prove that there exists a series SUM a_k with a_k>=0 and s_n = a_1 + a_2 + a_3 + .......+ a_n.
    I'm not sure where to start. I wrote out the sequence's terms:
    s_n = (s_1, s_2, s_3, .....s_n)
    Then I wrote;
    I'm unclear about exactly what I need to go for.
    Any clarifiction will be greatly appreciated.
  2. jcsd
  3. Oct 24, 2005 #2


    User Avatar
    Science Advisor
    Homework Helper

    Try to write the a's in terms of the s's. You've already got a_1=s_1. What must a_2 be? a_3? a_4? a_n?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook