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Homework Help: Mechanics using linear algebra helpa please.

  1. Feb 9, 2006 #1
    Question 20. The 3 equations I am using were given to me by my prof, so I can't imagine it being wrong. But you never know. Well as you can see my work is shown. My goal is to find the determinant of this 3 x 3 matrix, and from the determinant find the eigenvalues. Then using those eigenvalues to find the eigenvectors.The problem I run into when doing the determinant and then setting it equal 0 I get: -lamda^3 + 6lamda^2 - 10lamda + 4 = 0. Which I can't really see how to factor. So I can't imagine it having all real roots. And I am pretty sure it should have all real roots.

    Thanks for any help.

  2. jcsd
  3. Feb 9, 2006 #2


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    Homework Helper

    lambda = 2 is a factor and all three roots are real.
  4. Feb 9, 2006 #3
    Oh my gosh, you are the best. So now all I gotta do is remember how to do long division to get the other 2 roots :). Thx again.
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