Results 1 to 4 of 4

Math Help - Recurrance Relation

  1. #1
    Junior Member
    Joined
    Aug 2010
    Posts
    57

    Recurrance Relation

    I have asked to solve the linear non-homogeneous equation.

    A(n) = 8A(n-2) -16A(n-4) +F(n) , where F(n) = N^2*4^n

    All these n are subscript of A.

    I am not sure how to resolve that F(n).

    Can anyone help me.
    Last edited by kumaran5555; November 14th 2010 at 10:04 PM.
    Follow Math Help Forum on Facebook and Google+

  2. #2
    MHF Contributor FernandoRevilla's Avatar
    Joined
    Nov 2010
    From
    Madrid, Spain
    Posts
    2,162
    Thanks
    45
    Using a well known theorem and taking into account that 4 is not a root of the charactheristic equation, a particular
    solution for the complete equation has the form X(x)=(an^2+bn+c)4^n.
    Follow Math Help Forum on Facebook and Google+

  3. #3
    Junior Member
    Joined
    Aug 2010
    Posts
    57
    Can you please name the theorem used.
    Follow Math Help Forum on Facebook and Google+

  4. #4
    MHF Contributor FernandoRevilla's Avatar
    Joined
    Nov 2010
    From
    Madrid, Spain
    Posts
    2,162
    Thanks
    45
    If F(n)=a^nP_m(n) where P_m(n) is a polynomial of degree m, and a is not a root of the characteristic equation, then a particular solution for the complete is x(n)=a^nQ_m(n), where Q_m(n) is a polynomial of degree m. If a is a root of the characteristic equation with multiplicity s then, x(n)=a^mn^sQ_m(n).

    Regards.
    Follow Math Help Forum on Facebook and Google+

Similar Math Help Forum Discussions

  1. [SOLVED] limits of recurrance relation, log(a+b)
    Posted in the Calculus Forum
    Replies: 2
    Last Post: October 9th 2011, 10:24 AM
  2. Prove recurrance relation
    Posted in the Differential Equations Forum
    Replies: 9
    Last Post: December 15th 2010, 04:52 PM
  3. recurrance relation
    Posted in the Discrete Math Forum
    Replies: 1
    Last Post: May 13th 2009, 05:33 PM
  4. Solving recurrance relation using any technique
    Posted in the Discrete Math Forum
    Replies: 1
    Last Post: June 1st 2008, 04:11 AM
  5. Finding Function for a recurrance relation
    Posted in the Discrete Math Forum
    Replies: 4
    Last Post: March 17th 2008, 03:46 PM

Search Tags


/mathhelpforum @mathhelpforum