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The equation of conic section whose focu...

The equation of conic section whose focus is at (-1 , 0), directrix is the 4x-3y+2=0 and eccentricity `1//sqrt2`1, is

A

`34x^(2)+41y^(2)+24xy+84x+12y+46=0`

B

`34x^(2)+41y^(2)-24xy+84x+12y+46=0`

C

`34x^(2)+41y^(2)-24xy-84x-12y+46=0`

D

none of these.

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The correct Answer is:
To find the equation of the conic section given the focus, directrix, and eccentricity, we can follow these steps: ### Step-by-Step Solution: 1. **Identify the Given Information**: - Focus \( S = (-1, 0) \) - Directrix \( 4x - 3y + 2 = 0 \) - Eccentricity \( e = \frac{1}{\sqrt{2}} \) 2. **Let the Point on the Conic Section be \( P(h, k) \)**: - We will use the definition of a conic section, which states that the distance from the focus to a point \( P \) is equal to the eccentricity times the perpendicular distance from the point \( P \) to the directrix. 3. **Calculate the Distance from the Focus to the Point \( P \)**: - The distance \( SP \) from the focus \( S(-1, 0) \) to the point \( P(h, k) \) is given by: \[ SP = \sqrt{(h + 1)^2 + k^2} \] 4. **Calculate the Perpendicular Distance from the Point \( P \) to the Directrix**: - The formula for the distance from a point \( (h, k) \) to the line \( Ax + By + C = 0 \) is: \[ \text{Distance} = \frac{|Ah + Bk + C|}{\sqrt{A^2 + B^2}} \] - For the line \( 4x - 3y + 2 = 0 \), we have \( A = 4, B = -3, C = 2 \). Thus, the distance \( PM \) is: \[ PM = \frac{|4h - 3k + 2|}{\sqrt{4^2 + (-3)^2}} = \frac{|4h - 3k + 2|}{5} \] 5. **Set Up the Equation Using the Definition of Conic Section**: - According to the definition: \[ SP = e \cdot PM \] - Substituting the distances: \[ \sqrt{(h + 1)^2 + k^2} = \frac{1}{\sqrt{2}} \cdot \frac{|4h - 3k + 2|}{5} \] 6. **Square Both Sides to Eliminate the Square Root**: - Squaring both sides gives: \[ (h + 1)^2 + k^2 = \frac{1}{2} \cdot \left(\frac{|4h - 3k + 2|}{5}\right)^2 \] - This simplifies to: \[ (h + 1)^2 + k^2 = \frac{(4h - 3k + 2)^2}{50} \] 7. **Expand Both Sides**: - Left side: \[ (h + 1)^2 + k^2 = h^2 + 2h + 1 + k^2 \] - Right side: \[ \frac{(4h - 3k + 2)^2}{50} = \frac{16h^2 - 24hk + 9k^2 + 16h - 12k + 4}{50} \] 8. **Multiply Through by 50 to Eliminate the Denominator**: - This gives: \[ 50(h^2 + 2h + 1 + k^2) = 16h^2 - 24hk + 9k^2 + 16h - 12k + 4 \] 9. **Rearrange the Equation**: - Combine like terms: \[ 34h^2 + 41k^2 + 84h + 24hk + 46 = 0 \] 10. **Replace \( h \) and \( k \) with \( x \) and \( y \)**: - The final equation of the conic section is: \[ 34x^2 + 41y^2 + 84x + 24xy + 46 = 0 \] ### Final Answer: The equation of the conic section is: \[ 34x^2 + 41y^2 + 84x + 24xy + 46 = 0 \]

To find the equation of the conic section given the focus, directrix, and eccentricity, we can follow these steps: ### Step-by-Step Solution: 1. **Identify the Given Information**: - Focus \( S = (-1, 0) \) - Directrix \( 4x - 3y + 2 = 0 \) - Eccentricity \( e = \frac{1}{\sqrt{2}} \) ...
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OBJECTIVE RD SHARMA ENGLISH-PARABOLA-Chapter Test
  1. The equation of conic section whose focus is at (-1 , 0), directrix is...

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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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