Results 1 to 3 of 3

Math Help - solving for particular soln in nonhomogenous differential equation

  1. #1
    Member
    Joined
    Apr 2008
    From
    Seoul, South Korea
    Posts
    128

    solving for particular soln in nonhomogenous differential equation

    i'm solving the differential equation x''+x'-t=0 with the conditions x(0)=0 and x'(0)=0. i got that x_h=0 but i forget how to find x_p. can someone refresh me on how to find x_p in this case?
    Follow Math Help Forum on Facebook and Google+

  2. #2
    Global Moderator

    Joined
    Nov 2005
    From
    New York City
    Posts
    10,616
    Thanks
    9
    Quote Originally Posted by squarerootof2 View Post
    i'm solving the differential equation x''+x'-t=0 with the conditions x(0)=0 and x'(0)=0. i got that x_h=0 but i forget how to find x_p. can someone refresh me on how to find x_p in this case?
    Your equation is x'' + x = t.
    Note the RHS is a polynomial, thus, look for a solution of the form x_p=at+b.

    EDIT: Suppose the equation was x''+x' = t.
    Then look for a polynomial x_p = at^2+bt+c.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Flow Master
    mr fantastic's Avatar
    Joined
    Dec 2007
    From
    Zeitgeist
    Posts
    16,948
    Thanks
    5
    Quote Originally Posted by ThePerfectHacker View Post
    Your equation is x'' + x{\color{red}'} = t.
    Note the RHS is a polynomial, thus, look for a solution of the form x_p=at+b.
    The smallest of erratums (in red).

    Even obvious typos can cause anxiety and doubt amongst the ..... anxious.

    (I can hear TPH saying "Dash it!")
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. Replies: 1
    Last Post: February 13th 2010, 09:25 AM
  2. Solving a nonhomogenous D.E.
    Posted in the Differential Equations Forum
    Replies: 3
    Last Post: February 3rd 2010, 05:15 AM
  3. solving a nonhomogenous recursion
    Posted in the Discrete Math Forum
    Replies: 3
    Last Post: May 23rd 2009, 09:03 AM
  4. Nonhomogenous Linear Equation
    Posted in the Differential Equations Forum
    Replies: 4
    Last Post: February 27th 2009, 03:24 PM
  5. Nonhomogenous differencial equation
    Posted in the Calculus Forum
    Replies: 4
    Last Post: April 8th 2007, 07:31 AM

Search Tags


/mathhelpforum @mathhelpforum