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Manipal MET2021MathematicsDeterminants

In the determinant | array rrr 3 & x & -1 2 & -1 & 4 1 & y & -3 array | , the sum of the cofactors of x and y is

Options

  1. A-24
  2. B24
  3. C-4
  4. D4

Correct answer

C. -4

Step-by-step solution

Given, determinant | array rrr 3 & x & -1 2 & -1 & 4 1 & y & -3 array | Here, cofactor of x=10 and cofactor of y=-14 Their sum =-4

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