Steiner Ellipses and Variances

[Han de Bruijn]

http://faculty.evansville.edu/ck6/bstud/steiner.html

In the world of common mathematics, two so-called Steiner ellipses are
associated with an arbitrary triangle: Circumellipse and Inellipse:

http://mathworld.wolfram.com/SteinerEllipse.html

It is argued in this article that, instead of just two, a whole family
of Steiner ellipses can be associated with a triangle. All of them are
a multiple of a single ellipse called the Ellipse of Inertia / Ellipse
of Variances.

http://hdebruijn.soo.dto.tudelft.nl/jaar2011/steiners.pdf

Please scrutinize mathematics and spelling. Any comments are welcome.

Han de Bruijn