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Let e be the eccentricity of the ellipse...

Let e be the eccentricity of the ellipse represented by x=5 `(2cos theta+3 sin theta)`, y =4 (2 sin `theta`-3 cos `theta`), then `e^2` equals

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To find the value of \( e^2 \) for the ellipse represented by the parametric equations \( x = 5(2 \cos \theta + 3 \sin \theta) \) and \( y = 4(2 \sin \theta - 3 \cos \theta) \), we will follow these steps: ### Step 1: Rewrite the Parametric Equations We start with the given parametric equations: \[ x = 5(2 \cos \theta + 3 \sin \theta) \] \[ y = 4(2 \sin \theta - 3 \cos \theta) \] ### Step 2: Normalize the Equations Divide both equations by their respective coefficients: \[ \frac{x}{5} = 2 \cos \theta + 3 \sin \theta \quad \text{(Equation 1)} \] \[ \frac{y}{4} = 2 \sin \theta - 3 \cos \theta \quad \text{(Equation 2)} \] ### Step 3: Square and Add the Equations Now, we square both equations and add them: \[ \left(\frac{x}{5}\right)^2 + \left(\frac{y}{4}\right)^2 = (2 \cos \theta + 3 \sin \theta)^2 + (2 \sin \theta - 3 \cos \theta)^2 \] ### Step 4: Expand the Right Side Expanding the right side: \[ (2 \cos \theta + 3 \sin \theta)^2 = 4 \cos^2 \theta + 12 \cos \theta \sin \theta + 9 \sin^2 \theta \] \[ (2 \sin \theta - 3 \cos \theta)^2 = 4 \sin^2 \theta - 12 \sin \theta \cos \theta + 9 \cos^2 \theta \] Adding these two expansions: \[ 4 \cos^2 \theta + 9 \sin^2 \theta + 4 \sin^2 \theta + 9 \cos^2 \theta + 12 \cos \theta \sin \theta - 12 \sin \theta \cos \theta \] This simplifies to: \[ (4 + 9)(\cos^2 \theta + \sin^2 \theta) = 13 \] So we have: \[ \frac{x^2}{25} + \frac{y^2}{16} = 13 \] ### Step 5: Rearranging to Standard Form Rearranging gives us the standard form of the ellipse: \[ \frac{x^2}{325} + \frac{y^2}{208} = 1 \] ### Step 6: Identify \( a^2 \) and \( b^2 \) From the standard form, we identify: - \( a^2 = 325 \) - \( b^2 = 208 \) ### Step 7: Calculate the Eccentricity The eccentricity \( e \) of an ellipse is given by: \[ e^2 = 1 - \frac{b^2}{a^2} \] Substituting the values: \[ e^2 = 1 - \frac{208}{325} \] Calculating this gives: \[ e^2 = 1 - 0.64 = 0.36 \] ### Final Answer Thus, the value of \( e^2 \) is: \[ \boxed{0.36} \]
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MCGROW HILL PUBLICATION-ELLIPSE-Exercise (Level 2 Single Correct)
  1. If chords of contact of the tangent from two points (x1,y1) and (x2,y2...

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  2. If the normal at the point P(theta) to the ellipse x^2/14+y^2/5=1 inte...

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  3. Let E be the ellipse x^(2)/9 + y^(2)/4 = 1 and C be the circle x^(2) +...

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  4. If CF is perpendicular from the centre of the ellipse x^2/25+y^2/9=1 t...

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  5. If the tangent at the point P(theta) to the ellipse 16 x^2+11 y^2=256 ...

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  6. If lx+my+n=0 is an equation of the line joining the extremities of a p...

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  7. Let f be a strictly decreasing function defined on R such that f(x) gt...

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  8. Number of points from which two perpendicular tangents can be drawn to...

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  9. Let d be the perpendicular distance from the centre of the ellipse x^2...

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  10. Find the values of a for which three distinct chords drawn from (a ,0)...

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  11. Let C be the centre of the ellipse E whose equation is 3x^2 + 4y^2- 12...

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  12. Let e the eccentricity of the ellipse passing through A(1, -1) and hav...

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  13. Let e be the eccentricity of the ellipse represented by x=5 (2cos thet...

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  14. Number of points on the ellipse x^2/25+y^2/7=1 whose distance from the...

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  15. The number of lattice points (that is point with both coordinates as i...

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  16. Number of points on the ellipse x^2/a^2+y^2/b^2=1 at which the normal ...

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  17. Suppose the eccentricity of the ellipse x^2/(a^2+3)+ y^2/(a^2+4)=1 is ...

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  18. Suppose the ellipse x^2/2+y^2=1 and the ellipse x^2/5+y^2/a^2=1 where ...

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  19. Let e be the eccentricity of the ellipse x^2/16+y^2/b^2=1 where 0 lt ...

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