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The equation 2y^(2)+3y-4x-3=0 represents...

The equation `2y^(2)+3y-4x-3=0` represents a parabola for which

A

length of latus rectum is 4

B

equation of the axis is 4y + 3 = 0

C

equation of directrix is 2x + 1 = 0

D

equation of tangent at vertex is `x=-33/32`

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To solve the equation \(2y^2 + 3y - 4x - 3 = 0\) and find the directrix, equation of the axis, and length of the latus rectum, we can follow these steps: ### Step 1: Rearranging the equation We start with the equation: \[ 2y^2 + 3y - 4x - 3 = 0 \] Rearranging it gives: \[ 2y^2 + 3y = 4x + 3 \] ### Step 2: Completing the square for \(y\) To complete the square for the \(y\) terms, we can factor out the coefficient of \(y^2\): \[ 2\left(y^2 + \frac{3}{2}y\right) = 4x + 3 \] Now, we complete the square inside the parentheses: \[ y^2 + \frac{3}{2}y = \left(y + \frac{3}{4}\right)^2 - \frac{9}{16} \] So, substituting back, we have: \[ 2\left(\left(y + \frac{3}{4}\right)^2 - \frac{9}{16}\right) = 4x + 3 \] This simplifies to: \[ 2\left(y + \frac{3}{4}\right)^2 - \frac{9}{8} = 4x + 3 \] Adding \(\frac{9}{8}\) to both sides gives: \[ 2\left(y + \frac{3}{4}\right)^2 = 4x + 3 + \frac{9}{8} \] Converting \(3\) to eighths: \[ 3 = \frac{24}{8} \] So, we have: \[ 2\left(y + \frac{3}{4}\right)^2 = 4x + \frac{33}{8} \] ### Step 3: Dividing by 2 Now, divide the entire equation by 2: \[ \left(y + \frac{3}{4}\right)^2 = 2x + \frac{33}{16} \] Rearranging gives: \[ \left(y + \frac{3}{4}\right)^2 = 2\left(x + \frac{33}{32}\right) \] ### Step 4: Identifying the vertex From the equation \(\left(y - k\right)^2 = 4p\left(x - h\right)\), we can identify: - Vertex \((h, k) = \left(-\frac{33}{32}, -\frac{3}{4}\right)\) ### Step 5: Finding the axis of symmetry The axis of symmetry is given by the line: \[ y + \frac{3}{4} = 0 \quad \Rightarrow \quad y = -\frac{3}{4} \] ### Step 6: Finding the directrix The value of \(p\) (which is \(a\) in the standard form) is: \[ p = \frac{1}{2} \] The directrix is given by \(x = h - p\): \[ x = -\frac{33}{32} - \frac{1}{2} = -\frac{33}{32} - \frac{16}{32} = -\frac{49}{32} \] ### Step 7: Finding the length of the latus rectum The length of the latus rectum is given by: \[ 4p = 4 \times \frac{1}{2} = 2 \] ### Final Results - **Vertex**: \(\left(-\frac{33}{32}, -\frac{3}{4}\right)\) - **Equation of the Axis**: \(y = -\frac{3}{4}\) - **Directrix**: \(x = -\frac{49}{32}\) - **Length of Latus Rectum**: \(2\)
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FIITJEE-PARABOLA-SOLVED PROBLEMS (OBJECTIVE )
  1. If three distinct normals can be drawn to the parabola y^(2)-2y=4x-9 f...

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  2. The co-ordinates of the points on the barabola y^(2) =8x, which is at ...

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  3. AB is a focal chord of y^(2)=4x with A(2,2sqrt2). The radius of the ci...

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  4. Let S be the set of all possible values of parameter 'a' for which the...

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  5. If a normal chord at a point on the parabola y^(2)=4ax subtends a righ...

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  6. Find the equation of the straight lines touching both x^2+y^2=2a^2 and...

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  7. The equation 2y^(2)+3y-4x-3=0 represents a parabola for which

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  8. Consider the circle x^2+y^2=9 and the parabola y^2=8x. They intersect ...

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  9. Consider the circle x^2 + y^2 = 9 and the parabola y^2 = 8x. They inte...

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  10. Consider the circle x^2 + y^2 = 9 and the parabola y^2 = 8x. They inte...

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  11. If l and m are variable real number such that 5l^(2)+6m^(2)-4lm+3l=0, ...

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  12. If l and m are variable real number such that 5l^(2)+6m^(2)-4lm+3l=0, ...

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  13. Statement-1: The maximum value of |sqrt(x^(4)-3x^(2)-6x+13)-sqrt(x^(4)...

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  14. Normal at the point A(2, -4) intersect the parabola y^(2)=8x at the po...

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  15. Normals are drawn from the interior point P to the parabola y^(2)=4x s...

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  16. Match the following:

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  17. If normals to parabola y^(2)=4x at points A, B, C intersect at (11, 0)...

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  18. Column I : Parabola y^(2)=16x is given. In column I, 4 points (P) is g...

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  19. Column I : Parabola y^(2)=16x is given. In column I, 4 points (P) is g...

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  20. Column I : Parabola y^(2)=16x is given. In column I, 4 points (P) is g...

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