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If 2A=({:(2,1),(3,2):}), then what is A^...

If `2A=({:(2,1),(3,2):})`, then what is `A^(-1)` equal to ?

A

`({:(2,-1),(-3,2):})`

B

`(1)/(2)({:(2,-1),(-3,2):})`

C

`(1)/(4)({:(2,-1),(-3,2):})`

D

None of these

Text Solution

Verified by Experts

The correct Answer is:
D
Given, `2A=[(2,1),(3,2)]`
`A=((1,(1)/(2)),((3)/(2),1))`
`|A|=(1)/(4)`
`adjA=((1,-(1)/(2)),((-3)/(2),1))`
`A^(-1)=4((1,-(1)/(2)),((-3)/(2),1))=((4,-2),(-6,4))`
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NDA PREVIOUS YEARS-MATRICES & DETERMINANTS-MQS
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