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Find the inverse of the matrices (if it exists). [2-243] - Mathematics

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Question

Find the inverse of the matrices (if it exists).

`[(2,-2),(4,3)]`

Sum

Solution

Here A = `[(2,-2),(4,3)]`

So, adjA = `[(3,2),(-4,2)]`

`abs "A" = 6 + 8 = 14 ne 0 -> "A"^-1` exists.

C11 = (-1)1+1 (3) = 3

C12 = (-1)1+2 (4) = (-4)

C21 = (-1)2+1 (-2) = 2

C22 = (-1)2+2 (2) = 2

`"A"^-1 = 1/abs "A" ("adjA")`

`= 1/14 [(3,2),(-4,2)]`

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Chapter 4: Determinants - Exercise 4.5 [Page 132]

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NCERT Mathematics [English] Class 12
Chapter 4 Determinants
Exercise 4.5 | Q 5 | Page 132

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