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Select and write the most appropriate answer from the given alternatives in each of the following :
`A = {:((1,2),(3,4)):}` and A (adj A) = kI, then the value or 'k' is

A

2

B

`-2`

C

10

D

`-10`

Text Solution

Verified by Experts

The correct Answer is:
B
`A=[(1,2),(3,4)]`
`"Adj. of A"=[(4,-2),(-3,1)]`
`therefore" A(Adj. of A) = KI".`
`[(1,2),(3,4)][(4,-2),(-3,1)]=K[(1,0),(0,1)]`
`[(-2,0),(-,-2)]=[(K,0),(0,K)]`
`therefore" "K=-2`
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