मराठी

If for Any 2 X 2 Square Matrix A, A(Adj A) (8,0), (0,8) Then Write the Value of a

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प्रश्न

If for any 2 x 2 square matrix A, `A("adj"  "A") = [(8,0), (0,8)]`, then write the value of |A|

बेरीज
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उत्तर १

Given A (adj A = `[(8,0),(0,8)]`

we know that A(adj A) = |A| - I

|A|.I = `8[(1,0),(0,1)]`

`=> |A| = 8`

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उत्तर २

It is given that

A(adj A) = `[(8,0),(0,8)]`

⇒ A(adj A) = `8[(1,0),(0,1)]`

⇒ A(adj A) = 8I2          .....(1)

We know that for any square matrix A of order 2, we have

A(adj A) = |A|I2          .....(2)

From (1) and (2), we have

|A|=8

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2016-2017 (March) All India Set 1

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