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: Differentiate power series

  1. Apr 29, 2016 #1
    1. The problem statement, all variables and given/known data
    for d/dx(e^x) , the series should be start from 2 rather than 1 , right ? because when k = 1 , the circled part would become 0 , the series for (e^x) is 1 + x + ..........

    2. Relevant equations

    3. The attempt at a solution

    Attached Files:

  2. jcsd
  3. Apr 29, 2016 #2


    User Avatar
    Science Advisor
    Homework Helper

    The circled part is correct. There, the index of the sum notation is just shifted up by one, therefore the indices appearing in the term must be shifted down by one. If you compute the series terms by terms you should find that it's indeed the power expansion of ##e^x##.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted