Q17 of 108 Page 80

If , find k so that A2 = kA – 2I

A2 = A.A



Now, A2 = kA – 2I





Comparing the corresponding elements, we get,


3k -2 = 1


⇒ 3k = 3


⇒ k = 1


Therefore, the value of k is 1.


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