题目内容
(1)求证:平面GEF⊥平面PBC;
(2)求证:EG是PG与BC的公垂线段.
(1)O为△ABC的垂心;
(2)O在△ABC内;
(3)设SO=h,则++=.
求证:(1)平面GEF⊥平面PBC;
(2)GE是PG与BC的公垂线段.