Proving determinant property for arbitrary matrices

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In summary, the conversation discusses how to prove the statement "If A is a product of elementary matrices, show that det(adj(A))=(det(A))^(n-1)" and how to do it without assuming that A is a product of elementary matrices. The conversation also brings up the use of equivalent theorems for invertible matrices and how to set up the proof by considering A as an arbitrary matrix.
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Snowdeity
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Homework Statement


1) If A is a product of elementary matrices, show that det(adj(A))=(det(A))^(n-1)
2) Prove the above statement without the assumption on A


Homework Equations


Hmm... Know A*adj(A)=det(A)*In (i.e. the n by n identity matrix)



The Attempt at a Solution


Well I know the assumption implies the use of the equivalent theorems for invertible matrices...not sure how to set this up though. Have to show A as a n by n matrix in order to thoroughly prove it, but seems to get complicated quickly if trying to evaluate the adj(A)...
Anyone clue me in on this?
 
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  • #2
2) Prove the above statement without the assumption on AWell, I guess in this case we should consider A as an arbitrary matrix (not necessarily a product of elementary matrices). So far I have started with A*adj(A)=det(A)*In. But not sure where to go from here...
 

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