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Homework Help: Numerical linear Albebra

  1. Feb 4, 2007 #1
    1. The problem statement, all variables and given/known data

    In Matlab,

    Find the scalar (lamda) for which x+(lamda)v equals the solution obtained with the backslash operator \. Hence, x=B\b in matlab

    (This is another way of finding the inverse inv(B)... we could also use x=B\b)

    2. Relevant equations

    We have Bx = b

    B =
    [-1 2 -3
    0 4 1
    3 -6 9]

    b = [-12 -1 36]

    Null space v=[-14 -1 4]

    x = [-12.0000, -0.2143, -0.1429] <--- from B\b in matlab

    3. The attempt at a solution

    B*(x + (lamda)v) = b
    Bx + (lamda)Bv = b

    since v is the null space (lamda)Bv=0

    therefore, (lamda) could be anything?

    Is that correct?
  2. jcsd
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