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प्रश्न
Find the inverse of the matrices (if it exists).
`[(2,-2),(4,3)]`
उत्तर
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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