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Consider three points P = (-sin (beta-al...

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 < pi/4` Then

A

P lies on the line segment RQ

B

Q lies on the segment PR

C

R lies on the line segment PR

D

P,Q,R are non-collinear

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To solve the problem of determining the relationship between the points \( P \), \( Q \), and \( R \), we will follow these steps: ### Step 1: Define the Points We have three points defined as follows: - \( P = (-\sin(\beta - \alpha), -\cos(\beta)) \) - \( Q = (\cos(\beta - \alpha), \sin(\beta)) \) - \( R = (\cos(\beta - \alpha + \theta), \sin(\beta - \theta)) \) ### Step 2: Express the Coordinates Let’s express the coordinates of each point in terms of \( x \) and \( y \): - For point \( P \): - \( x_1 = -\sin(\beta - \alpha) \) - \( y_1 = -\cos(\beta) \) - For point \( Q \): - \( x_2 = \cos(\beta - \alpha) \) - \( y_2 = \sin(\beta) \) - For point \( R \): - \( x_3 = \cos(\beta - \alpha + \theta) \) - \( y_3 = \sin(\beta - \theta) \) ### Step 3: Expand the Coordinates of Point R Using the angle addition formulas, we can expand the coordinates of point \( R \): - For \( x_3 \): \[ x_3 = \cos(\beta - \alpha + \theta) = \cos(\beta - \alpha)\cos(\theta) - \sin(\beta - \alpha)\sin(\theta) \] Substituting \( x_2 \) and \( y_1 \): \[ x_3 = x_2 \cos(\theta) - (-y_1) \sin(\theta) = x_2 \cos(\theta) + y_1 \sin(\theta) \] - For \( y_3 \): \[ y_3 = \sin(\beta - \theta) = \sin(\beta)\cos(\theta) - \cos(\beta)\sin(\theta) \] Substituting \( y_2 \) and \( y_1 \): \[ y_3 = y_2 \cos(\theta) - (-y_1) \sin(\theta) = y_2 \cos(\theta) + y_1 \sin(\theta) \] ### Step 4: Check for Collinearity To determine if points \( P \), \( Q \), and \( R \) are collinear, we can check if the area formed by these points is zero. The area can be calculated using the determinant: \[ \text{Area} = \frac{1}{2} \left| x_1(y_2 - y_3) + x_2(y_3 - y_1) + x_3(y_1 - y_2) \right| \] ### Step 5: Substitute the Coordinates Substituting the coordinates into the area formula: \[ \text{Area} = \frac{1}{2} \left| (-\sin(\beta - \alpha))(\sin(\beta) - (y_2 \cos(\theta) + y_1 \sin(\theta))) + (\cos(\beta - \alpha))((y_2 \cos(\theta) + y_1 \sin(\theta)) - (-\cos(\beta))) + (\cos(\beta - \alpha + \theta)((-\cos(\beta)) - \sin(\beta))) \right| \] ### Step 6: Analyze the Result If the area is non-zero, then the points are non-collinear. Given the constraints \( 0 < \alpha, \beta, \theta < \frac{\pi}{4} \), we can conclude that the points \( P \), \( Q \), and \( R \) do not lie on the same line. ### Conclusion Thus, the final conclusion is that points \( P \), \( Q \), and \( R \) are non-collinear.

To solve the problem of determining the relationship between the points \( P \), \( Q \), and \( R \), we will follow these steps: ### Step 1: Define the Points We have three points defined as follows: - \( P = (-\sin(\beta - \alpha), -\cos(\beta)) \) - \( Q = (\cos(\beta - \alpha), \sin(\beta)) \) - \( R = (\cos(\beta - \alpha + \theta), \sin(\beta - \theta)) \) ...
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