JEE Mains · Maths · STD 12 - 3 and 4 . metrices and determinant
If \(A=\) \(\left[ {\begin{array}{*{20}{c}}{5a}&{ - b}\\3&2\end{array}} \right]\) and \(A\;adj\;A = A\;{A^T},\) then \(5a+b \) to :
- A \(4\)
- B \(13\)
- C \(-1\)
- D \(5\)
Answer & Solution
Correct Answer
(D) \(5\)
Step-by-step Solution
Detailed explanation
\(A=\left[\begin{array}{cc}{5 a} & {-b} \\ {3} & {2}\end{array}\right]\) and \(A^{T}=\left[\begin{array}{cc}{5 a} & {3} \\ {-b} & {2}\end{array}\right]\)…
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