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Still Harder Temple Geometry Problems
P A F
S C
Figure 6.29. A plane P cuts a right circular cylinder, producing an ellipse with major axis AB. The center of the ellipse is O. A sphere with center S intersects the plane containing the ellipse, producing a circle with center C. The points of tangency between the circle and the ellipse are where the “equator� of the sphere (dashed circle) intersects the ellipse.
O G
B
A F b S C O G
B
2b
D
Figure 6.30. Side view of plane P cutting cylinder. The segment AB is the major axis of ellipse = 2a. The diameter of the cylinder is the minor axis of the ellipse = 2b.