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Question
If A and B are square matrices of order 3 such that |A| = –1 and |B| = 3, find the value of |3AB|
Solution
Given |A| = –1
|B| = 3
Given A and B are square matrices of order 3.
∴ |kAB| = k3 |AB|
Here k = 3
∴ |3AB| = 33 |AB|
= 27 |AB|
= 27(–1)(3)
= – 81
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