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The length of the axes of the conic 9x^2...

The length of the axes of the conic `9x^2 + 4y^2 - 6x + 4y +1=0`, are

A

`(1)/(2),9`

B

`3,(2)/(5)`

C

`1,(2)/(3)`

D

`3,2`

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To find the lengths of the axes of the conic given by the equation \(9x^2 + 4y^2 - 6x + 4y + 1 = 0\), we will follow these steps: ### Step 1: Rearranging the equation We start with the given equation: \[ 9x^2 + 4y^2 - 6x + 4y + 1 = 0 \] We can rearrange it to: \[ 9x^2 - 6x + 4y^2 + 4y + 1 = 0 \] Next, we will move the constant term to the other side: \[ 9x^2 - 6x + 4y^2 + 4y = -1 \] ### Step 2: Completing the square for \(x\) and \(y\) Now, we will complete the square for the \(x\) and \(y\) terms. **For \(x\):** The terms involving \(x\) are \(9x^2 - 6x\). We factor out 9: \[ 9(x^2 - \frac{2}{3}x) \] To complete the square, we take half of \(-\frac{2}{3}\) (which is \(-\frac{1}{3}\)), square it (getting \(\frac{1}{9}\)), and add and subtract it inside the parentheses: \[ 9\left(x^2 - \frac{2}{3}x + \frac{1}{9} - \frac{1}{9}\right) = 9\left((x - \frac{1}{3})^2 - \frac{1}{9}\right) \] This simplifies to: \[ 9(x - \frac{1}{3})^2 - 1 \] **For \(y\):** The terms involving \(y\) are \(4y^2 + 4y\). We factor out 4: \[ 4(y^2 + y) \] To complete the square, we take half of \(1\) (which is \(\frac{1}{2}\)), square it (getting \(\frac{1}{4}\)), and add and subtract it inside the parentheses: \[ 4\left(y^2 + y + \frac{1}{4} - \frac{1}{4}\right) = 4\left((y + \frac{1}{2})^2 - \frac{1}{4}\right) \] This simplifies to: \[ 4(y + \frac{1}{2})^2 - 1 \] ### Step 3: Substitute back into the equation Now substituting back, we have: \[ 9\left((x - \frac{1}{3})^2 - \frac{1}{9}\right) + 4\left((y + \frac{1}{2})^2 - \frac{1}{4}\right) = -1 \] This simplifies to: \[ 9(x - \frac{1}{3})^2 - 1 + 4(y + \frac{1}{2})^2 - 1 = -1 \] Combining the constants: \[ 9(x - \frac{1}{3})^2 + 4(y + \frac{1}{2})^2 - 2 = -1 \] Adding 2 to both sides: \[ 9(x - \frac{1}{3})^2 + 4(y + \frac{1}{2})^2 = 1 \] ### Step 4: Dividing by the right-hand side Now we divide the entire equation by 1: \[ \frac{9(x - \frac{1}{3})^2}{1} + \frac{4(y + \frac{1}{2})^2}{1} = 1 \] This can be rewritten as: \[ \frac{(x - \frac{1}{3})^2}{\frac{1}{9}} + \frac{(y + \frac{1}{2})^2}{\frac{1}{4}} = 1 \] ### Step 5: Identifying parameters \(a\) and \(b\) From the standard form of the ellipse: \[ \frac{(x - h)^2}{a^2} + \frac{(y - k)^2}{b^2} = 1 \] we can identify: - \(a^2 = \frac{1}{9} \Rightarrow a = \frac{1}{3}\) - \(b^2 = \frac{1}{4} \Rightarrow b = \frac{1}{2}\) ### Step 6: Finding lengths of the axes The lengths of the axes are given by: - Length of the major axis = \(2b = 2 \times \frac{1}{2} = 1\) - Length of the minor axis = \(2a = 2 \times \frac{1}{3} = \frac{2}{3}\) ### Final Answer Thus, the lengths of the axes of the ellipse are: - Major axis: 1 - Minor axis: \(\frac{2}{3}\)

To find the lengths of the axes of the conic given by the equation \(9x^2 + 4y^2 - 6x + 4y + 1 = 0\), we will follow these steps: ### Step 1: Rearranging the equation We start with the given equation: \[ 9x^2 + 4y^2 - 6x + 4y + 1 = 0 \] We can rearrange it to: ...
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OBJECTIVE RD SHARMA ENGLISH-ELLIPSE-Chapter Test
  1. The length of the axes of the conic 9x^2 + 4y^2 - 6x + 4y +1=0, are

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  2. Find the maximum area of an isosceles triangle inscribed in the ellip...

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  3. A tangent to the ellipse x^2+4y^2=4 meets the ellipse x^2+2y^2=6 at P&...

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  4. The distance of a point on the ellipse (x^2)/6+(y^2)/2=1 from the cent...

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  5. If the minor axis of an ellipse subtends an angle of 60^(@) at each fo...

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  6. Let Sa n dS ' be two foci of the ellipse (x^2)/(a^2)+(y^2)/(b^2)=1 . I...

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  7. The equation of the normal at the point P (2, 3) on the ellipse 9x^(2)...

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  8. For the ellipse 3x^(2) + 4y^(2) + 6x - 8y - 5 = 0 the eccentrically, i...

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  9. Let S, S' be the focil and BB' be the minor axis of the ellipse (x^(2)...

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  10. If the length of the latusrectum of the ellipse x^(2) tan^(2) theta + ...

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  11. if vertices of an ellipse are (-4,1),(6,1) and x-2y=2 is focal chord t...

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  12. If (-4, 3) and (8, 3) are the vertices of an ellipse whose eccentricit...

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  13. If the chord joining points P(alpha) and Q(beta) on the ellipse ((x^...

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  14. If P(alpha,beta) is a point on the ellipse (x^2)/(a^2)+(y^2)/(b^2)=1...

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  15. The tangent at any point P on the ellipse meets the tangents at the ve...

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  16. P is a point on the circle x^(2) + y^(2) = c^(2). The locus of the mid...

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  17. The equation of the locus of the poles of normal chords of the ellipse...

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  18. The locus of mid-points of focal chords of the ellipse (x^2)/(a^2)+(y^...

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  19. The locus of a point whose polar with respect to the ellipse (x^2)/(a^...

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  20. if the chord of contact of tangents from a point P to the hyperbola x...

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  21. The locus of the poles of tangents to the auxiliary circle with respec...

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