Let `A`
be a `3xx3`
square matrix such that
`A(a d j\ A)=2I`
, where `I`
is the identity matrix.
Write the value of `|a d j\ A|`
.
Text Solution
Verified by Experts
Consider the following identity A(adjA)=∣A∣I.
Thus comparing it with the above equation gives us `∣A∣=2`
Now `∣adjA∣=∣A∣^(n−1)`
where n is the order of the square matrix.
Here 'n' is 3, therefore,
`∣adjA∣=∣A∣^(3−1)=∣A∣^2=2^2=4`.
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