Inversion

by v_Enhance, Feb 28, 2011, 1:11 AM

Quote:
A circle passes through point A of triangle ABC. It intersects AB at M, AC at N, and BC at D and E. From left to right, BC has points B, D, E, and C. You are given the sides of the triangle, the lengths of BD and EC, and the radius of the circle. Find a nontrivial relationship between these lengths.

I attempted to invert around A. The resulting diagram was meh.

Comment

6 Comments

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How did you learn inversion? I found the wiki page pretty confusing.

by dragon96, Feb 28, 2011, 2:37 AM

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Dr. Vandervelde had a course on it at MathPath.

by v_Enhance, Feb 28, 2011, 3:44 AM

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That was the best class of those I took.

by 3333, Mar 1, 2011, 7:14 AM

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Hey, v_Enhance, you should learn geo.

You should sign up for olympiad geometry (not too late yet) with ksun and I.

It's fun.

There are a bunch of us WOOT+OlyGeoers

by yugrey, Mar 2, 2011, 12:05 AM

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Hey, v_Enhance, you should learn geo.

You should sign up for olympiad geometry (not too late yet) with ksun and I.

It's fun.

There are a bunch of us WOOT+OlyGeoers

by yugrey, Mar 2, 2011, 12:05 AM

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Um... "you should learn geo?"

...yugrey...

.

by AwesomeToad, Mar 4, 2011, 3:19 AM

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