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Help System of equations!

  1. Oct 25, 2004 #1
    Help!! System of equations!

    For a natural number define the n*n matrix A = (aij) by setting aij = min(i,j). Write down the matrix a for a few values of n = 2,3,4...... Show that A is invertible and find its inverse.
    Hence or otherwise show that the system of equations Ax =b , where x=(x1,....xn) and b=(b1.....bn) has a unique solution.

    Anyone help with how to solve that?
    Rob and Joanna!
  2. jcsd
  3. Oct 25, 2004 #2


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    Have you tried n=2, 3, and 4 at least?

    Write them down and try to reduce to the identity by row operations. Should be easy. You shold be able to find inverse in each case too.
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