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If A=[(1,"sin"(alpha)/2),(-"sin"(alpha)/...

If `A=[(1,"sin"(alpha)/2),(-"sin"(alpha)/2,1]` then adj A is

A

`[(-1,"sin"(alpha)/2),(-"sin"(alpha)/2,-1)]`

B

`[(1,-"sin"(alpha)/2),("sin"(alpha)/2,1)]`

C

`[(1,-"sin"(alpha)/2),(-"sin"(alpha)/2,1)]`

D

None of these

Text Solution

Verified by Experts

The correct Answer is:
B
Now cofactors of matrix A are ltbRgt `C_(11)=1,C_(12)=-sin alpha//2`
`C_(21)=sin alpha//2, C_(22)=1`
`adjA=[(1 sin alpha//2),(-sin alpha//21)]^(T)`
`adj A=[(1,-"sin"(alpha)/2),("sin"(alpha)/2,1)]`
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