WBJEE · Maths · Determinants
Let \(\mathrm{A}=\left(\begin{array}{ccc}3-\mathrm{t} & 1 & 0 \\ -1 & 3-\mathrm{t} & 1 \\ 0 & -1 & 0\end{array}\right)\) and \(\operatorname{det} \mathrm{A}=5\), then
- A \(\mathrm{t}=1\)
- B \(\mathrm{t}=2\)
- C \(t=-1\)
- D \(\mathrm{t}=-2\)
Answer & Solution
Correct Answer
(D) \(\mathrm{t}=-2\)
Step-by-step Solution
Detailed explanation
Hint: \(|\mathrm{A}|=\left|\begin{array}{ccc}3-\mathrm{t} & 1 & 0 \\ -1 & 3-\mathrm{t} & 1 \\ 0 & -1 & 0\end{array}\right|=3-\mathrm{t}=5, \mathrm{t}=-2\)
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