AP EAMCET · Maths · Matrices
If \(A=\left[\begin{array}{lll}a & 1 & 2 \\ 1 & 2 & b \\ c & 1 & 3\end{array}\right]\) and \(\operatorname{Adj} A=\left[\begin{array}{ccc}7 & -1 & -5 \\ -3 & 9 & 5 \\ 1 & -3 & 5\end{array}\right]\) then \(a^2+b^2+c^2=\)
- A 10
- B 14
- C 11
- D 29
Answer & Solution
Correct Answer
(A) 10
Step-by-step Solution
Detailed explanation
\(A=\left|\begin{array}{lll}a & 1 & 2 \\ 1 & 2 & b \\ c & 1 & 3\end{array}\right|, \operatorname{Adj} A=\left|\begin{array}{ccc}7 & -1 & -5 \\ -3 & 9 & 5 \\ 1 & -3 & 5\end{array}\right|\) We know,…
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