Y by
In acute triangle
with circumcenter
and orthocenter
, let
be an arbitrary point on the circumcircle of triangle
such that
does not lie on line
and that line
is not parallel to line
. Let
be the point on the circumcircle of triangle
such that
is perpendicular to
, and let
be the point on line
such that
. Let
and
be the points on the circumcircle of triangle
such that
is a diameter, and
and
are parallel. Let
be the midpoint of
.
(a) Show that
and
are perpendicular.
(b) Show that
and
are perpendicular.
























(a) Show that


(b) Show that

