The locus of the orthocenter of the triangle formed by the focal chord of the parabola y2=4ax and the normal drawn at its extermities is
y2=a(x−3a)
The normals at the extremities of focal chord meet at right angle. So orthocenter is the point of intersection of normals.
If P(at21,2at1),Q(at22,2at2) then t1t2=−1 point of intersection of normals.
h=a(t21+t22+t1t2+2)
k=−at1t2(t1+t2)