SOLUTION: if A is a square matrix of order 3 and |adj A| = 64. find |2A|

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Question 1024740: if A is a square matrix of order 3 and |adj A| = 64. find |2A|
Answer by robertb(5830) About Me  (Show Source):
You can put this solution on YOUR website!
If abs%28adjA%29+=+64, and A is a square matrix of order 3, then abs%28adjA%29+=+abs%28A%29%5E2+=+64
==> |A| = 8 or |A| = -8
==> |2A| = 2^3*8 = 64 or |2A| =-2^3*8 = -64.