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Homework Help: Two-Point Boundary Value Problem

  1. May 7, 2010 #1
    1. The problem statement, all variables and given/known data

    y'' + ßy = 0, y'(0)=0, y'(L)=0

    2. Relevant equations

    Meh

    3. The attempt at a solution

    I so already did the ß>1 and ß<1; I'm stuck on the ß=0. It seems easy enough. y'' = 0 -----> y' = A -----> 0=A, 0=A (from the two initial conditions) ------> No non-trivial solution.

    But.....

    The answer in the back of the book says ß0=0, y0(x)=1; .....


    ???????
     
  2. jcsd
  3. May 7, 2010 #2

    LCKurtz

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    Starting with y'' = 0 you need to integrate twice to get y, getting two constants.
     
  4. May 7, 2010 #3
    The boundaries it gives me are in terms of y' :wink:


    Of course I know
    y'' = 0 -----> y' = B ----> y = Ax + b
     
  5. May 7, 2010 #4

    LCKurtz

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    But the point is: does your boundary condition force only the trivial solution or can you get a non-trivial solution in this case?
     
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