Why is det(C)=det(A)^(n-1) for cofactors and determinants?

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SUMMARY

The equation det(C) = det(A)^(n-1) holds true for an n-by-n matrix A, where C represents the matrix of cofactors of A. This relationship is derived from the equation AC = (det A)I, indicating that the product of matrix A and its cofactor matrix C results in a scalar multiple of the identity matrix I. Additionally, when the determinant of A is non-zero, the inverse of A can be expressed as A^(-1) = (1/det A)C, reinforcing the connection between determinants and cofactors.

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Unusualskill
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Any1 can explain to me why det(C)=det(A)^(n-1)
where A is n-by-n matrix and C is the matrix of cofactors of A.
I have been thinking, any 1 can help?thx!
 
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This follows from the equation AC=(det A)I, or equivalently A-1= (1/det A)C (if det A≠0).
 

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