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The normals at the ends of the latusrect...

The normals at the ends of the latusrectum of the parabola `y^(2)=4ax" are (a, 2a) and (a, -2a)"`.

A

`pi/6`

B

`pi/4`

C

`pi/3`

D

`pi/2`

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To solve the problem, we need to find the angle between the normals drawn at the ends of the latus rectum of the parabola given by the equation \( y^2 = 4ax \). The ends of the latus rectum are given as the points \( (a, 2a) \) and \( (a, -2a) \). ### Step-by-Step Solution: 1. **Identify the points on the parabola**: The ends of the latus rectum for the parabola \( y^2 = 4ax \) are given as: - Point P: \( (a, 2a) \) - Point Q: \( (a, -2a) \) 2. **Equation of the normal at point P**: The general equation of the normal to the parabola at a point \( (x_1, y_1) \) is given by: \[ y - y_1 = -\frac{y_1}{2a}(x - x_1) \] Substituting \( (x_1, y_1) = (a, 2a) \): \[ y - 2a = -\frac{2a}{2a}(x - a) \] Simplifying this, we have: \[ y - 2a = -1(x - a) \implies y - 2a = -x + a \implies x + y = 3a \] This is the equation of the normal at point P. 3. **Equation of the normal at point Q**: Similarly, for point Q \( (a, -2a) \): \[ y - (-2a) = -\frac{-2a}{2a}(x - a) \] Simplifying this: \[ y + 2a = 1(x - a) \implies y + 2a = x - a \implies x - y = 3a \] This is the equation of the normal at point Q. 4. **Finding the slopes of the normals**: From the equations of the normals: - For the normal at P: \( x + y = 3a \) can be rewritten as \( y = -x + 3a \) which has a slope \( m_1 = -1 \). - For the normal at Q: \( x - y = 3a \) can be rewritten as \( y = x - 3a \) which has a slope \( m_2 = 1 \). 5. **Finding the angle between the normals**: The angle \( \theta \) between two lines with slopes \( m_1 \) and \( m_2 \) can be found using the formula: \[ \tan \theta = \left| \frac{m_1 - m_2}{1 + m_1 m_2} \right| \] Substituting \( m_1 = -1 \) and \( m_2 = 1 \): \[ \tan \theta = \left| \frac{-1 - 1}{1 + (-1)(1)} \right| = \left| \frac{-2}{0} \right| \] Since the denominator is zero, this indicates that the lines are perpendicular, hence: \[ \theta = 90^\circ \quad \text{or} \quad \theta = \frac{\pi}{2} \text{ radians} \] ### Final Answer: The angle between the normals at the ends of the latus rectum of the parabola \( y^2 = 4ax \) is \( \frac{\pi}{2} \) radians.

To solve the problem, we need to find the angle between the normals drawn at the ends of the latus rectum of the parabola given by the equation \( y^2 = 4ax \). The ends of the latus rectum are given as the points \( (a, 2a) \) and \( (a, -2a) \). ### Step-by-Step Solution: 1. **Identify the points on the parabola**: The ends of the latus rectum for the parabola \( y^2 = 4ax \) are given as: - Point P: \( (a, 2a) \) - Point Q: \( (a, -2a) \) ...
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OBJECTIVE RD SHARMA ENGLISH-PARABOLA-Chapter Test
  1. The normals at the ends of the latusrectum of the parabola y^(2)=4ax" ...

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  2. If y=2x+k is a tangent to the curve x^(2)=4y, then k is equal to

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  3. The normal drawn at a point (a t1 2,-2a t1) of the parabola y^2=4a x m...

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  4. The mid-point of the chord 2x+y-4=0 of the parabola y^(2)=4x is

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  5. The two ends of latusrectum of a parabola are the points (3, 6) and (-...

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  6. Prove that the locus of the middle points of all chords of the parabol...

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  7. The focus of the parabola x^2-8x+2y+7=0 is

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  8. The point of contact of the line x-2y-1=0 with the parabola y^(2)=2(x-...

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  9. Find the number of distinct normals that can be drawn from (-2,1) to t...

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  10. At what point on the parabola y^2=4x the normal makes equal angle with...

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  11. Three normals to the parabola y^2= x are drawn through a point (C, O) ...

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  12. The normal chord of a parabola y^2= 4ax at the point P(x1, x1) subten...

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  13. AB, AC are tangents to a parabola y^2=4ax; p1, p2, p3 are the lengths...

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  14. The circles on the focal radii of a parabola as diameter touch: A) th...

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  15. If the normals from any point to the parabola y^2=4x cut the line x=2 ...

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  16. about to only mathematics

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  17. The equation of the tangent to the parabola y^(2)=8x which is perpendi...

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  18. the tangent drawn at any point P to the parabola y^2= 4ax meets the di...

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  19. about to only mathematics

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  20. The parabola y^(2)=4ax passes through the point (2,-6). Find the lengt...

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  21. A variable circle passes through the fixed point (2, 0) and touches y-...

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