Answer with Step-by-step explanation:
We are given that
A and B are matrix.
A.We know that for two square matrix A and B
Then, 
Therefore, it is true.
B. det A is the product of diagonal entries in A.
It is not true for all matrix.It is true for upper triangular matrix.
Hence, it is false.
C.

When is a factor of the characteristics polynomial of A then -5 is an eigenvalue of A not 5.
Hence, it is false.
D.An elementary row operation on A does not change the determinant.
It is true because when an elementary operation applied then the value of matrix A does not change.
I don’t see the problems you want me to solve. Sorry
Answer:-8d -9dd
Step-by-step explanation:I looked it up :)I'm not good at math so yeahhh but I hope this is right but if not I'll try again
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Answer:
what the choices?
Step-by-step explanation: