ExamBro
ExamBro
JEE Advanced · Mathematics · 9. Straight Lines

Consider three points \(P=(-\sin (\beta-\alpha),-\cos \beta), Q=(\cos (\beta-\alpha), \sin \beta)\) and \(R=(\cos (\beta-\alpha+\theta), \sin (\beta-\theta)\), where \(0 < \alpha, \beta, \theta < \frac{\pi}{4}\). Then,

  1. A
    \(P\) lies on the line segment \(R Q\)
  2. B
    \(Q\) lies on the line segment \(P R\)
  3. C
    \(R\) lies on the line segment \(Q P\)
  4. D
    \(P, Q, R\) are non- collinear
Verified Solution

Answer & Solution

Correct Answer

(D)
\(P, Q, R\) are non- collinear

Step-by-step Solution

Detailed explanation

For collinear points
\[
\Delta=\left|\begin{array}{ccc}
-\sin (\beta-\alpha) & -\cos \beta & 1 \\
\cos (\beta-\alpha) & \sin \beta & 1 \\
\cos (\beta-\alpha+\theta) & \sin (\beta-\theta) & 1
\end{array}\right|
\]
Clearly, \(\Delta \neq 0\) for any value of \(\alpha, \beta, \theta\), hence points are non-collinear.
Same subject
Explore more questions on app
From JEE Advanced
Explore more questions on app