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If A= [[2,-1],[-1,2]] and I is the unit ...

If `A= [[2,-1],[-1,2]]` and `I` is the unit matrix of order 2 , then `A^2` is equal to

A

`3 A-4 I`

B

`A+I`

C

`4 A-3 I`

D

`A-I`.

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A
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HIMALAYA PUBLICATION-MATRICES AND DETERMINANTS-QUESTION BANK
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