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Homework Help: Linear algebra adjoint, determinant

  1. Feb 12, 2013 #1
    1. The problem statement, all variables and given/known data

    Given A=[1 2 1; 0 4 3; 1 2 2]
    determine the (2,3) entry of A-1 by computing a quotient of two determinants.

    This problem confused me a bit, do they just want us to divide the adj(A) by the det(A) in order which would give us A-1 and just state the (2,3) entry from there?



    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Feb 12, 2013 #2


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    Homework Helper

    You don't need to compute the whole A^(-1). But as you say, they just want you to compute adj(A)(2,3)/det(A). Just the one entry of A^(-1).
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