JEE Mains · Maths · STD 12 - 3 and 4 . metrices and determinant
Let \(\alpha, \beta \in \mathbb{R}\) be such that the system of linear equations
\(x + 2y + z = 5\)
\(2x + y + \alpha z = 5\)
\(8x + 4y + \beta z = 18\)
has no solution. Then \(\dfrac{\beta}{\alpha}\) is equal to :
- A \(-4\)
- B \(4\)
- C \(8\)
- D \(-8\)
Answer & Solution
Correct Answer
(B) \(4\)
Step-by-step Solution
Detailed explanation
The given system of linear equations is: \(x + 2y + z = 5\) \(2x + y + \alpha z = 5\) \(8x + 4y + \beta z = 18\) For the system to have no solution, the determinant of the coefficient matrix \(D\) must be zero.…
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