JEE Mains · Maths · STD 12 - 10. vector algebra
If \((2,3,9),(5,2,1),(1, \lambda, 8)\) and \((\lambda, 2,3)\) are coplanar, then the product of all possible values of \(\lambda\) is.
- A \(\frac{21}{2}\)
- B \(\frac{59}{8}\)
- C \(\frac{57}{8}\)
- D \(\frac{95}{8}\)
Answer & Solution
Correct Answer
(D) \(\frac{95}{8}\)
Step-by-step Solution
Detailed explanation
\(A (2,3,9) ; B (5,2,1) ; C (1, \lambda, 8) ; D (\lambda, 2,3)\) \([\overline{ AB } \overline{ AC } \overline{ AD }]=0\) \(\left|\begin{array}{ccc}3 & -1 & -8 \\ -1 & \lambda-3 & -1 \\ \lambda-2 & -1 & -6\end{array}\right|=0\)…
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