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Inverse Matrix Proof

  1. Nov 2, 2004 #1
    I'm having a bit of a struggle with my assignment.

    I'm supposed to find what is x in AxB = (B-1A-1)-1 .

    I'm stumped at what to do with this. My friend said that x is I (identity matrix), but he is unable to prove it as well. My linear algebra class just recently started doing this topic and I haven't fully absorbed the subject yet.

    Any hints or tips would be helpful though.

  2. jcsd
  3. Nov 2, 2004 #2


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    Hi, you should try to simplify the right hand side, starting with the outermost -1. What rules do you have for the inverse of a product of matrices?
  4. Nov 3, 2004 #3


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    (B-1A-1)-1 is the matrix C such that C(B-1A-1)= I. Since you have that equal to AxB, how do you get AxB(B-1A-1)= I??
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