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If k in Rot h e ndet{a d j(k In)} is eq...

If `k in R_ot h e ndet{a d j(k I_n)}` is equal to `K^(n-1)` b. `K^(n(n-1))` c. `K^n` d. `k`

A

`k^(n-1)`

B

`k^(n(n-1))`

C

`k^(n)`

D

`k`

Text Solution

Verified by Experts

The correct Answer is:
B
`(KI_(n))` adj. `(kI_(n))=|kI_(n)|I_(n)" "["using A (adj. A)"=|A|I]`
adj. `(kI_(n))=k^(n-1) I_(n)`
`|"adj. "(kI_(n))|=k^(n(n-1))`
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