16 Jul
2015
16 Jul
'15
12:43 p.m.
Nice one! I think that can easily be made rigorous, say with a Taylor expansion to the first order. —Dan
On Jul 16, 2015, at 11:30 AM, Allan Wechsler <acwacw@gmail.com> wrote:
My informal proof is that if the two angles were unequal, and you shifted the contact paint along the ellipse toward the smaller angle, you'd be making the distance shorter.
On Thu, Jul 16, 2015 at 2:10 PM, Dan Asimov <asimov@msri.org <mailto:asimov@msri.org>> wrote:
If we define an ellipse by the locus of points whose sum-of-distances to two given points is a fixed constant, what is the shortest proof that these two segments make equal angles with the tangent line?
(Assuming the ellipse surrounds a positive area.)