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If A=[[cosalpha, sinalpha], [-sinalpha, ...

If `A=[[cosalpha, sinalpha], [-sinalpha, cosalpha]] and A(adjA)=[[k, 0], [0, k]]`, then k=

A

`sinalphacosalpha`

B

`cos2alpha`

C

`0`

D

`1`

Text Solution

Verified by Experts

The correct Answer is:
D
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