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: Theoretical/non-tedious question about Frobenius method

  1. Apr 18, 2012 #1


    User Avatar

    When using the Frobenius method of solving differential equations using power series solutions, I get a solution

    y = (indicial_stuff) + (infinite_summation_stuff) = 0

    for a differential equation differential_stuff = 0.

    WHY is it that I can say

    (indicial_stuff) = 0?


    y = (indicial_stuff) * (infinite_summation_stuff) = 0

    (NOTICE THE MULTIPLICATION INSTEAD OF ADDITION) then it would make sense to me that

    (indicial_stuff) = 0

    but with the addition, I cannot make sense of this.

    I tried to generalize this question and hope that I haven't made it more confusing but, if I have made the question confusing, please tell me and I will clear things up as best as I can.

    Basically, I'm just asking for the reason why this – the isolation of the indicial polynomial equation (and the other summation portion) - is justified.

    Any input would be greatly appreciated!
    Thanks in advance!
  2. jcsd
  3. Apr 19, 2012 #2


    User Avatar

    The answer to my question was: "by equating coefficients."
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook