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Determine all minors and cofactors of A = [-1 4 8; -9 2 -1; 3 -7 5].

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Final answer:

The minors and cofactors of the matrix A = [-1 4 8; -9 2 -1; 3 -7 5] can be found by finding the determinant of each submatrix. The minors are the determinants of the 2x2 submatrices formed by removing each row and column. The cofactors are obtained by multiplying the minors by alternating signs (+ and -).

Step-by-step explanation:

The minors and cofactors of the matrix A = [-1 4 8; -9 2 -1; 3 -7 5] can be found by finding the determinant of each submatrix.

The minors are the determinants of the 2x2 submatrices formed by removing each row and column. The cofactors are obtained by multiplying the minors by alternating signs (+ and -).

The minors and cofactors of the matrix A are:

  • Minor of (1,1): 5, Cofactor of (1,1): 5
  • Minor of (1,2): -9, Cofactor of (1,2): 9
  • Minor of (1,3): 2, Cofactor of (1,3): -2
  • Minor of (2,1): 7, Cofactor of (2,1): -7
  • Minor of (2,2): -34, Cofactor of (2,2): 34
  • Minor of (2,3): -21, Cofactor of (2,3): -21
  • Minor of (3,1): -44, Cofactor of (3,1): 44
  • Minor of (3,2): -59, Cofactor of (3,2): -59
  • Minor of (3,3): -73, Cofactor of (3,3): 73
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