ADGEOM 202

[Paul Yiu]:

Dear Francisco Javier,

[FJ]: Viktor Kitaysky has drawn my attention on the point X(600):
In  Hyainthos 2348 we can read:

The radical center of the three circles ABaCa, BCbAb, and CAcBc
is the point
(a^2(a^2(b^2+c^2)-b^2c^2))/(2a^2-(2b^2-bc+2c^2)): ... : ...)

This point appear in ETC as X(600), but the coordinates seems wrong.

The correct barycentric coordinates are

(a(a+R)((s-a)R+SA):b(b+R)((s-b)R+SB):c(c+R)((s-c)R+SC))

where R is the circumradius of the triangle.

*** I have no record of the calculations, and can only check with the Hyacinthos messages. I agree with your coordinates.

Best regards,
Sincerely
Paul