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Find the inverse of the following matrix (if they exist):(1327) - Mathematics and Statistics

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प्रश्न

Find the inverse of the following matrix (if they exist):

`((1,3),(2,7))`

बेरीज

उत्तर

Let A = `[(1,3),(2,7)]`

∴ |A| = `|(1,3),(2,7)|` = 7 - 6 = 1 ≠ 0

∴ A-1 exists.

Consider AA-1 = I

∴ `[(1,3),(2,7)] "A"^-1 = [(1,0),(0,1)]`

By R2 - 2R1, we get,

`[(1,3),(0,1)] "A"^-1 = [(1,0),(-2,1)]`

By R1 - 3R2 we get,

`[(1,0),(0,1)] "A"^-1 = [(7,-3),(-2,1)]`

A-1 = `[(7,-3),(-2,1)]`

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पाठ 2: Matrics - Miscellaneous exercise 2 (A) [पृष्ठ ५३]

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