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If A=[(-2,3),(1,1)] then |A^(-1)|=?...

If `A=[(-2,3),(1,1)]` then `|A^(-1)|`=?

A

-5

B

`(-1)/5`

C

`1/(25)`

D

25

Text Solution

Verified by Experts

The correct Answer is:
B
`"AA"^(-1)=1rArr |"AA"^(-1)|=|I|rArr|A|.|A^(-1)|=1rArr|A^(-1)|=1/(|A|)`
`|A|=|(2,-3),(1,1)|=(-2-3)=(-5)rArr|A^(-1)|=-1/5`
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