## Question

The radius of the circle passing through the foci of the ellipse

9*x*^{2} + 16*y*^{2} = 144 and having its centre at (0, 3), is

### Solution

4

We have,

The eccentricity *e* of the ellipse is given by

So, the coordinates of the foci are .

∴ Radius of the circle

#### SIMILAR QUESTIONS

Tangent is drawn to the ellipse , then the value of θ such that sum of intercepts on axes made by the tangent is minimum is

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An ellipse has OB as a semi-minor axis, *F*, *F*’ as its foci and the angle ∠*FBF*’ is a right angle. Then, the eccentricity of the ellipse is