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Question
Find the cofactors of the elements of the matrix
`[(-1, 2),(-3, 4)]`
Solution
Given, matrix is `[(-1, 2),(-3, 4)]`
Here a11 = –1; ∴ N11 = 4 and A11 = (–1)1+1 (4) = 4
a12 = 2; ∴ N12 = –3 and A12 = (–1)1+2 (–3) = 3
a21 = –3; ∴ N21 = 2 and A21 = (–1)2+1 (2) = –2
a22 = 4; ∴ N22 = –1 and A22 = (–1)2+2 (–1) = –1
∴ The required cofactors are 4, 3, –2, –1.
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