O is the circumcenter of acute triangle ABC, H is the Orthocenter. AD is perpendicular to BC, EF is the perpendicular bisector of AO,D,E on the BC. Prove that the circumcircle of triangle ADE passes through the midpoint of OH.
Let a, b, and c be real numbers greater
than zero. define an xy coordinate system
such that A=(0,a), B=(b,0), C=(c,0),
D=(0,0), E=(e,0), F=(f,g), H=(0,h),
K=(k,0), L=(i,j), M=(m,n), and P=(u,v).
Where F, K, L, M, and N are the midpoints
of line segments AO, BC, AB, OH, and AE
respectively.
It is easy, but tedious, to solve for all
the coordinates in terms of a, b, and c.
Then all that is needed is to verify that
PM^2 = PD^2.

Posted by Bractals
on 20130203 16:16:12 