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: Variation of Parameters on a 1st Order DE

  1. Sep 26, 2010 #1
    1. The problem statement, all variables and given/known data

    Solve xy' - y = x3 (1) by using variation of parameters.

    3. The attempt at a solution

    Solving the homogeneous version of (1) gives

    yh = c1x

    Now we are to seek

    yp = A(x)*x (2)

    from (2)

    y'2 = A'*x +A

    plugging into (1) we have:

    x[A'*x + A] - Ax = x3

    A'x2 = x3

    A' = x

    => A(x) = x2/2 +C2

    =>yp= C2x + x3/2


    Oh ... nevermind! :biggrin:
     
    Last edited: Sep 26, 2010
  2. jcsd
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Can you offer guidance or do you also need help?
Draft saved Draft deleted