If A = , find |A|.

GIVEN:

Now,


We know that a determinant of a 3 x 3 matrix is calculated as


.


= 1[-9 – (-3)(4)] – 1[2(-9) – (-3)(5)] – 2[2(4) – 1(5)]


= 1[-9 + 12] – 1[-18 + 15] – 2[8 – 5]


= 1[3] – 1[-3] – 2[3]


= 3 + 3 – 6


= 0


Ans. |A| = 0


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