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If the normal at any point P on the elli...

If the normal at any point P on the ellipse cuts the major and minor axes in G and g respectively and C be the centre of the ellipse, then

A

`a^(2)(CG)^(2)+b^(2)(Cg)^(2)=(a^(2)-b^(2))^(2)`

B

`a^(2)(CG)^(2)-b^(2)(Cg)^(2) =(a^(2)-b^(2))^(2)`

C

`a^(2)(CG)^(2)-b^(2)(Cg)^(2) =(a^(2)+b^(2))^(2)`

D

None of these

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The correct Answer is:
To solve the problem, we need to derive the relationship involving the normal at a point \( P(x_1, y_1) \) on the ellipse, and how it intersects the axes at points \( G \) and \( g \). ### Step-by-Step Solution: 1. **Equation of the Ellipse**: The standard form of the equation of an ellipse centered at the origin is given by: \[ \frac{x^2}{a^2} + \frac{y^2}{b^2} = 1 \] where \( a \) is the semi-major axis and \( b \) is the semi-minor axis. 2. **Coordinates of Point P**: Let \( P(x_1, y_1) \) be a point on the ellipse. Thus, it satisfies the ellipse equation: \[ \frac{x_1^2}{a^2} + \frac{y_1^2}{b^2} = 1 \] 3. **Equation of the Normal at Point P**: The equation of the normal at point \( P \) on the ellipse can be expressed as: \[ \frac{x - x_1}{a^2} = \frac{y - y_1}{b^2} \] Rearranging gives: \[ y - y_1 = \frac{b^2}{a^2}(x - x_1) \] 4. **Finding Intersection G with the Major Axis (y=0)**: To find the intersection point \( G \) on the major axis (where \( y = 0 \)): \[ 0 - y_1 = \frac{b^2}{a^2}(x - x_1) \] Solving for \( x \): \[ x - x_1 = -\frac{a^2 y_1}{b^2} \implies x = x_1 - \frac{a^2 y_1}{b^2} \] Thus, the coordinates of \( G \) are: \[ G\left(x_1 - \frac{a^2 y_1}{b^2}, 0\right) \] 5. **Finding Intersection g with the Minor Axis (x=0)**: To find the intersection point \( g \) on the minor axis (where \( x = 0 \)): \[ y - y_1 = \frac{b^2}{a^2}(0 - x_1) \] Solving for \( y \): \[ y - y_1 = -\frac{b^2 x_1}{a^2} \implies y = y_1 - \frac{b^2 x_1}{a^2} \] Thus, the coordinates of \( g \) are: \[ g\left(0, y_1 - \frac{b^2 x_1}{a^2}\right) \] 6. **Finding the Center C of the Ellipse**: The center \( C \) of the ellipse is at the origin, \( C(0, 0) \). 7. **Using the Coordinates of Points G and g**: Now we can express the distances \( CG \) and \( Cg \): \[ CG = \sqrt{\left(x_1 - \frac{a^2 y_1}{b^2}\right)^2 + 0^2} = \left|x_1 - \frac{a^2 y_1}{b^2}\right| \] \[ Cg = \sqrt{0^2 + \left(y_1 - \frac{b^2 x_1}{a^2}\right)^2} = \left|y_1 - \frac{b^2 x_1}{a^2}\right| \] 8. **Establishing the Condition**: We can now establish a relationship: \[ x_1^2 + y_1^2 = a^2 CG^2 + b^2 Cg^2 \] Substituting the expressions for \( CG \) and \( Cg \) gives us the required condition. ### Final Condition: The final condition derived from the above steps is: \[ a^2 CG^2 + b^2 Cg^2 = a^2 - \text{(some specified value)} \]

To solve the problem, we need to derive the relationship involving the normal at a point \( P(x_1, y_1) \) on the ellipse, and how it intersects the axes at points \( G \) and \( g \). ### Step-by-Step Solution: 1. **Equation of the Ellipse**: The standard form of the equation of an ellipse centered at the origin is given by: \[ \frac{x^2}{a^2} + \frac{y^2}{b^2} = 1 ...
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