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Homework Help: Determinant problem

  1. Oct 26, 2007 #1
    [SOLVED] Determinant problem

    1. The problem statement, all variables and given/known data
    If det(A) = 7, then what is det(4 A-1)?
    where A is 3*3 matrix

    2. Relevant equations

    3. The attempt at a solution

    No idea about this, please give me some hint.
  2. jcsd
  3. Oct 26, 2007 #2
    This is just collecting properties about determinants. If you scale one of your rows (or columns) by some scalar what is the determinant of the resulting matrix? Now, realize that 4A is multiplying every row by 4. Assuming A has an inverse, what is the determinant of the inverse?
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