JEE Mains · Maths · STD 12 - 3 and 4 . metrices and determinant
Let \(A+2 B=\left[\begin{array}{ccc}1 & 2 & 0 \\ 6 & -3 & 3 \\ -5 & 3 & 1\end{array}\right]\) and \(2 A - B =\left[\begin{array}{ccc}2 & -1 & 5 \\ 2 & -1 & 6 \\ 0 & 1 & 2\end{array}\right] .\) If \(\operatorname{Tr}( A )\) denotes the sum of all diagonal elements of the matrix \(A ,\) then \(\operatorname{Tr}( A )-\operatorname{Tr}( B )\) has value equal to
- A \(1\)
- B \(2\)
- C \(0\)
- D \(3\)
Answer & Solution
Correct Answer
(B) \(2\)
Step-by-step Solution
Detailed explanation
\(A +2 B =\left(\begin{array}{ccc}1 & 2 & 0 \\ 6 & -3 & 3 \\ -5 & 3 & 1\end{array}\right) \quad \ldots(1)\) \(2 A - B =\left(\begin{array}{ccc}2 & -1 & 5 \\ 2 & -1 & 6 \\ 0 & 1 & 2\end{array}\right)\)…
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