Collinear Apexes of Cones

Initializing live version
Download to Desktop

Requires a Wolfram Notebook System

Interact on desktop, mobile and cloud with the free Wolfram Player or other Wolfram Language products.

Given three spheres, wrap a cone around each pair. Then the apexes of the three cones lie on a line.

Contributed by: Izidor Hafner (November 2012)
Open content licensed under CC BY-NC-SA


Snapshots


Details

Proof: place the spheres on a flat table, and put a board on top of them. The table and board define two planes that are tangent to all three spheres. The cones and their apexes also touch both planes. The apexes must lie on the intersection of these two planes, which is a line.

Reference

[1] L. A. Graham, Ingenious Mathematical Problems and Methods, New York: Dover, 1959 pp. 198–199.



Feedback (field required)
Email (field required) Name
Occupation Organization
Note: Your message & contact information may be shared with the author of any specific Demonstration for which you give feedback.
Send