Inspect the following without finding the determinant:
1.
[1 0 0 0]
[0 1 0 0]
[0 0 1 0]
[0 0 0 - 2]
2. [1 0 0 0]
[0 1 0 0]
[0 0 0 1]
[0 0 1/4 0]
1
Expert's answer
2021-06-07T14:37:50-0400
If all elements of a row (or column) of a determinant are multiplied by some scalar number k, the value of the new determinant is k times of the given determinant.
If any two row (or two column) of a determinant are interchanged the value of the determinant is multiplied by −1.
In identity matrix aii=1, and all other elements = 0, hence the determinant is 1.
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