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The sum fo the squares of the perpendicu...

The sum fo the squares of the perpendicular on any tangent to the ellipse `x^(2)/a^(2) + y^(2)/b^(2) = 1` from two points on the mirror axis, each at a distance `sqrt(a^(2) - b^(2))` from the centre, is

A

`2a^(2)`

B

`2b^(2)`

C

`a^(2) + b^(2)`

D

`a^(2) - b^(2)`

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To solve the problem, we need to find the sum of the squares of the perpendiculars from two points on the minor axis of the ellipse \( \frac{x^2}{a^2} + \frac{y^2}{b^2} = 1 \) to any tangent line to the ellipse. The points are located at a distance of \( \sqrt{a^2 - b^2} \) from the center along the minor axis. ### Step-by-Step Solution: 1. **Identify the Points on the Minor Axis:** The minor axis of the ellipse is along the y-axis. The points on the minor axis at a distance of \( \sqrt{a^2 - b^2} \) from the center (0,0) are: \[ P(0, ae) \quad \text{and} \quad Q(0, -ae) \] where \( e = \sqrt{1 - \frac{b^2}{a^2}} \) is the eccentricity of the ellipse. 2. **Equation of the Tangent to the Ellipse:** The equation of any tangent to the ellipse can be expressed in the form: \[ y = mx + \sqrt{a^2 m^2 + b^2} \] Rearranging gives us: \[ mx - y + \sqrt{a^2 m^2 + b^2} = 0 \] 3. **Calculate the Length of the Perpendicular from Point P:** The length of the perpendicular \( p_1 \) from point \( P(0, ae) \) to the tangent line is given by the formula: \[ p_1 = \frac{|mx_1 - y_1 + c|}{\sqrt{m^2 + 1}} \] Substituting \( x_1 = 0 \) and \( y_1 = ae \): \[ p_1 = \frac{|m(0) - ae + \sqrt{a^2 m^2 + b^2}|}{\sqrt{m^2 + 1}} = \frac{|-ae + \sqrt{a^2 m^2 + b^2}|}{\sqrt{m^2 + 1}} \] 4. **Calculate the Length of the Perpendicular from Point Q:** Similarly, for point \( Q(0, -ae) \): \[ p_2 = \frac{|m(0) - (-ae) + \sqrt{a^2 m^2 + b^2}|}{\sqrt{m^2 + 1}} = \frac{|ae + \sqrt{a^2 m^2 + b^2}|}{\sqrt{m^2 + 1}} \] 5. **Sum of the Squares of the Perpendiculars:** Now we need to find \( p_1^2 + p_2^2 \): \[ p_1^2 + p_2^2 = \left( \frac{|-ae + \sqrt{a^2 m^2 + b^2}|}{\sqrt{m^2 + 1}} \right)^2 + \left( \frac{|ae + \sqrt{a^2 m^2 + b^2}|}{\sqrt{m^2 + 1}} \right)^2 \] This simplifies to: \[ p_1^2 + p_2^2 = \frac{|-ae + \sqrt{a^2 m^2 + b^2}|^2 + |ae + \sqrt{a^2 m^2 + b^2}|^2}{m^2 + 1} \] 6. **Expanding the Squares:** Let \( k = \sqrt{a^2 m^2 + b^2} \): \[ p_1^2 + p_2^2 = \frac{(k - ae)^2 + (k + ae)^2}{m^2 + 1} \] Expanding this gives: \[ = \frac{(k^2 - 2k \cdot ae + a^2e^2) + (k^2 + 2k \cdot ae + a^2e^2)}{m^2 + 1} = \frac{2k^2 + 2a^2e^2}{m^2 + 1} \] 7. **Substituting \( k \):** Recall \( k^2 = a^2 m^2 + b^2 \): \[ p_1^2 + p_2^2 = \frac{2(a^2 m^2 + b^2) + 2a^2e^2}{m^2 + 1} \] 8. **Simplifying Further:** Since \( b^2 = a^2(1 - e^2) \): \[ p_1^2 + p_2^2 = \frac{2a^2(m^2 + b^2 + e^2)}{m^2 + 1} \] Noting that \( b^2 + a^2e^2 = a^2 \): \[ = \frac{2a^2}{m^2 + 1} \] 9. **Final Result:** The final result simplifies to: \[ p_1^2 + p_2^2 = 2a^2 \] ### Final Answer: The sum of the squares of the perpendiculars from the two points on the minor axis to any tangent to the ellipse is \( 2a^2 \).

To solve the problem, we need to find the sum of the squares of the perpendiculars from two points on the minor axis of the ellipse \( \frac{x^2}{a^2} + \frac{y^2}{b^2} = 1 \) to any tangent line to the ellipse. The points are located at a distance of \( \sqrt{a^2 - b^2} \) from the center along the minor axis. ### Step-by-Step Solution: 1. **Identify the Points on the Minor Axis:** The minor axis of the ellipse is along the y-axis. The points on the minor axis at a distance of \( \sqrt{a^2 - b^2} \) from the center (0,0) are: \[ P(0, ae) \quad \text{and} \quad Q(0, -ae) ...
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