Triangle ABC is inscribed in circle with center O. Let P be a point on arc AB which does not contain point C. Perpendicular from point P on line BO intersects side AB in point S, and side BC in T. Perpendicular from point P on line AO intersects side AB in point Q, and side AC in R.
(i) Prove that triangle PQS is isosceles
(ii) Prove that QRPQā=PQSTā perpendicularisoscelesgeometry