# Right circular cone with elliptical section

Geometry Level 5

A right circular cone having apex angle $$\alpha=69^\circ$$ is thoroughly cut by an inclined plane to generate an elliptical section (as shown by the dotted closed curve in the figure below) . If the angle between axis of cone & the plane is $$\theta=73^\circ$$ then find out the acute angle ($$<\theta$$ in degree) between the plane & the line joining the center of ellipse to the apex of cone.

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