COMEDK · Maths · 22. Determinants
Value of the determinant of a matrix A of order \(3 \times 3\) is 7 . Then the value of the determinant formed by the cofactors of matrix A is
- A \(49\)
- B \(343\)
- C \(7\)
- D \(14\)
Answer & Solution
Correct Answer
(A) \(49\)
Step-by-step Solution
Detailed explanation
Let \(A\) be a square matrix of order \(n \times n\). The matrix formed by the cofactors of \(A\) is denoted by \(C\). The property relating the determinant of the cofactor matrix to the determinant of the original matrix is given by \(|C| = |A|^{n-1}\). In this problem, the…
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