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If normal at any point P to ellipse `(x^2)/(a^2) + (y^2)/(b^2) = 1(a > b)` meet the x & y axes at A and B respectively. Such that `(PA)/(PB) = 3/4` , then eccentricity of the ellipse is:

A

`1/3`

B

`1/2`

C

`1/4`

D

`1/9`

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To solve the problem, we need to find the eccentricity of the ellipse given the condition that the ratio of the distances from point P to points A and B is \( \frac{3}{4} \). ### Step-by-Step Solution: 1. **Understanding the ellipse**: The equation of the ellipse is given by: \[ \frac{x^2}{a^2} + \frac{y^2}{b^2} = 1 \] where \( a > b \). The major axis is along the x-axis, and the minor axis is along the y-axis. 2. **Finding the coordinates of point P**: Let point P on the ellipse be represented in parametric form as: \[ P(a \cos \theta, b \sin \theta) \] 3. **Equation of the normal at point P**: The equation of the normal to the ellipse at point P can be derived using the formula: \[ y - b \sin \theta = -\frac{b^2 \cos \theta}{a^2 \sin \theta} (x - a \cos \theta) \] Rearranging gives: \[ \frac{b^2 \cos \theta}{a^2 \sin \theta} x + y = b \sin \theta + \frac{b^2 \cos \theta}{a^2 \sin \theta} a \cos \theta \] 4. **Finding intersection with the x-axis (A)**: Set \( y = 0 \) to find the x-intercept (point A): \[ 0 = b \sin \theta + \frac{b^2 \cos \theta}{a^2 \sin \theta} a \cos \theta - \frac{b^2 \cos \theta}{a^2 \sin \theta} x \] Solving for \( x \): \[ x_A = \frac{a^2 \sin^2 \theta + b^2 \cos^2 \theta}{b \sin \theta} \] 5. **Finding intersection with the y-axis (B)**: Set \( x = 0 \) to find the y-intercept (point B): \[ y_B = b \sin \theta - \frac{b^2 \cos \theta}{a^2 \sin \theta} a \cos \theta \] 6. **Using the given ratio**: We know that: \[ \frac{PA}{PB} = \frac{3}{4} \] This gives us: \[ PA = \sqrt{(x_A - a \cos \theta)^2 + (0 - b \sin \theta)^2} \] \[ PB = \sqrt{(0 - a \cos \theta)^2 + (y_B - b \sin \theta)^2} \] 7. **Setting up the equation**: Substitute \( PA \) and \( PB \) into the ratio: \[ \frac{PA}{PB} = \frac{3}{4} \] Squaring both sides and simplifying will yield a relationship between \( a \) and \( b \). 8. **Finding eccentricity**: The eccentricity \( e \) of the ellipse is defined as: \[ e = \sqrt{1 - \frac{b^2}{a^2}} \] Using the relationship derived from the ratio, we can solve for \( e \). 9. **Final calculation**: After simplification, we find that: \[ 3a^2 = 4b^2 \quad \Rightarrow \quad \frac{b^2}{a^2} = \frac{3}{4} \] Therefore, substituting into the eccentricity formula: \[ e = \sqrt{1 - \frac{3}{4}} = \sqrt{\frac{1}{4}} = \frac{1}{2} \] ### Conclusion: The eccentricity of the ellipse is: \[ \boxed{\frac{1}{2}} \]

To solve the problem, we need to find the eccentricity of the ellipse given the condition that the ratio of the distances from point P to points A and B is \( \frac{3}{4} \). ### Step-by-Step Solution: 1. **Understanding the ellipse**: The equation of the ellipse is given by: \[ \frac{x^2}{a^2} + \frac{y^2}{b^2} = 1 ...
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