COMEDK · Maths · 22. Determinants
Let \(A = [a_{ij}]\) be a square matrix of order \(3 \times 3\), where the elements are defined as
\(a_{ij} = \begin{cases} i - 2j & \text{if } i = j \\ 0 & \text{if } i > j \\ 1 & \text{if } i < j \end{cases}\) then the value of \(|A^t|\) is
- A \(-5\)
- B \(1\)
- C \(-6\)
- D \(-11\)
Answer & Solution
Correct Answer
(C) \(-6\)
Step-by-step Solution
Detailed explanation
Given the elements of the \(3 \times 3\) matrix \(A = [a_{ij}]\): For the diagonal elements (\(i = j\)): \(a_{11} = 1 - 2(1) = -1\) \(a_{22} = 2 - 2(2) = -2\) \(a_{33} = 3 - 2(3) = -3\) For elements below the principal diagonal (\(i > j\)): \(a_{21} = 0, a_{31} = 0, a_{32} = 0\)…
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