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If A=adjA, then |A| is equal to (A is in...

If `A=adj`A, then |A| is equal to (A is invertible)

A

1

B

0

C

`|A^(-1)|`

D

None of these

Text Solution

Verified by Experts

The correct Answer is:
A
`A(adjA)=|A|limpliesA^(2)=|A|l`
`implies|A|^(2)=|A|^(n)` i.e., `|A|^(n-2)=1`
`implies|A|=1` if n is odd or `+-1` if n is even.
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