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!

Variation of parameters problem, very BIG, but i think i'm right so far! Diff EQ

  1. Feb 20, 2006 #1
    OKay everyone, this is a big f'ing problem (to me anyways) and its only worth 1 point! But i'm doing it anyways. So here was my attempt, everything seems to be working out like it should but look at what u1 came out too, what am i going to do with that mess? Also do u see any mistakes? Thanks!
    http://img86.imageshack.us/img86/6803/lastscan0rh.jpg [Broken]
    http://img86.imageshack.us/img86/2782/lastscan22bs.jpg [Broken]
    Last edited by a moderator: May 2, 2017
  2. jcsd
  3. Feb 20, 2006 #2


    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    That IS a lot of work. Are you sure that's how you're expected to solve these problem? Our friend Lagrange cooked up a crispy formula just for these occasions. It says that if [itex]y_1(t)[/itex] and [itex]y_2(t)[/itex] are linearly independant solution to the homogeneous equation y'' + p(t)y' + q(t)y = 0, then a particular solution to the inhomogeneous equation y'' + p(t)y' + q(t)y=g(t) is

    [tex]Y(t) = -y_1 \int \frac{y_2 g}{W(y_1,y_2)}dt + y_2\int\frac{y_1 g}{W(y1,y_2)}dt[/tex]
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Similar Threads - Variation parameters problem Date
Variation of parameters Monday at 10:59 PM
A Wronskian- variation of Params Problem Nov 23, 2016
Variation of Parameters problem Mar 9, 2011
Variation of Parameter Problem Feb 20, 2009
Differential Equations - Variation of Parameters problem Oct 30, 2008