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The form of a Matrix M help.

  1. Apr 19, 2004 #1
    I need help finding the form of the matrix M, heres the question:
    (n and n+1 is a subscript):

    Xn =

    Xn+1 = MXn

    M is a 2 x 2 matrix. The question says - What is the precise form of the matrix M?
  2. jcsd
  3. Apr 19, 2004 #2


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    You are going to need more information than that! For one thing, are An and Bn numbers? The real information you need is some definition of xn. Just "xn+1= Mxn isn't enough. Do you have formulas for An and Bn?
  4. Apr 19, 2004 #3
    o sorry, the other information given is that the vectors with two components are A, & B so yes they are numbers. (which represents the concentration of a reactant-for the question).
    After one time step (where n represents the timesteps thus n+1) 80% of A is transformed into B while 60% of B is tranformed into A.

    Does this help?
  5. Apr 23, 2004 #4


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    So An+1= 0.2An+ 0.6Bn (the 20% of A left over after 80% is transformed into B and the 60% of B that is transformed into A) and
    Bn+1= 0.8An+ 0.4Bn.

    Looks like M=
    [0.2 0.6]
    [0.8 0.4]
    Last edited: Apr 23, 2004
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