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The area between the parabola y^2 = 4x ,...

The area between the parabola `y^2 = 4x` , normal at one end of latusrectum and X-axis in sq.units is

A

`60^(@)`

B

less then `60^(@)`

C

more then`60^(@)`

D

less then `45^(@)`

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To find the area between the parabola \( y^2 = 4x \), the normal at one end of the latus rectum, and the x-axis, we can follow these steps: ### Step 1: Identify the parameters of the parabola The given parabola is \( y^2 = 4x \). Here, we can identify \( a = 1 \) because it is in the form \( y^2 = 4ax \). **Hint:** The value of \( a \) helps in determining the coordinates of the latus rectum. ### Step 2: Find the coordinates of the latus rectum The latus rectum of the parabola \( y^2 = 4ax \) has endpoints at \( (a, 2a) \) and \( (a, -2a) \). For \( a = 1 \), the coordinates are: - \( (1, 2) \) - \( (1, -2) \) **Hint:** The latus rectum is a vertical line segment through the focus of the parabola. ### Step 3: Determine the normal at one end of the latus rectum We will find the normal at the point \( (1, 2) \). The slope \( m \) of the tangent at this point can be calculated using the derivative of the parabola. From the equation \( y^2 = 4x \), we differentiate implicitly: \[ 2y \frac{dy}{dx} = 4 \] Thus, \[ \frac{dy}{dx} = \frac{2}{y} \] At the point \( (1, 2) \), \[ \frac{dy}{dx} = \frac{2}{2} = 1 \] The slope of the normal is the negative reciprocal: \[ m = -1 \] **Hint:** The slope of the normal line is perpendicular to the slope of the tangent line. ### Step 4: Write the equation of the normal line Using the point-slope form of the line equation: \[ y - y_1 = m(x - x_1) \] Substituting \( (x_1, y_1) = (1, 2) \) and \( m = -1 \): \[ y - 2 = -1(x - 1) \] This simplifies to: \[ y = -x + 3 \] **Hint:** The normal line intersects the x-axis where \( y = 0 \). ### Step 5: Find the x-intercept of the normal line Setting \( y = 0 \) in the equation of the normal: \[ 0 = -x + 3 \] Thus, \[ x = 3 \] So the x-intercept is \( (3, 0) \). **Hint:** The x-intercept is where the normal line meets the x-axis. ### Step 6: Calculate the area between the parabola, the normal, and the x-axis The area can be divided into two parts: 1. The area under the parabola from \( x = 0 \) to \( x = 1 \). 2. The area of the triangle formed by the points \( (1, 0) \), \( (3, 0) \), and \( (3, 2) \). **Area under the parabola:** To find the area under the parabola from \( x = 0 \) to \( x = 1 \): \[ \text{Area}_\text{parabola} = \int_0^1 \sqrt{4x} \, dx = \int_0^1 2\sqrt{x} \, dx \] Calculating the integral: \[ = 2 \cdot \left[ \frac{2}{3} x^{3/2} \right]_0^1 = 2 \cdot \frac{2}{3} = \frac{4}{3} \] **Area of the triangle:** The base of the triangle is from \( x = 1 \) to \( x = 3 \) (length = 2) and the height is 2 (from \( (3, 0) \) to \( (3, 2) \)): \[ \text{Area}_\text{triangle} = \frac{1}{2} \times \text{base} \times \text{height} = \frac{1}{2} \times 2 \times 2 = 2 \] ### Step 7: Total area Now, we add both areas: \[ \text{Total Area} = \text{Area}_\text{parabola} + \text{Area}_\text{triangle} = \frac{4}{3} + 2 = \frac{4}{3} + \frac{6}{3} = \frac{10}{3} \] **Final Answer:** The area between the parabola \( y^2 = 4x \), the normal at one end of the latus rectum, and the x-axis is \( \frac{10}{3} \) square units. ---

To find the area between the parabola \( y^2 = 4x \), the normal at one end of the latus rectum, and the x-axis, we can follow these steps: ### Step 1: Identify the parameters of the parabola The given parabola is \( y^2 = 4x \). Here, we can identify \( a = 1 \) because it is in the form \( y^2 = 4ax \). **Hint:** The value of \( a \) helps in determining the coordinates of the latus rectum. ### Step 2: Find the coordinates of the latus rectum ...
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OBJECTIVE RD SHARMA ENGLISH-PARABOLA-Chapter Test
  1. The area between the parabola y^2 = 4x , normal at one end of latusrec...

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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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