The ABC triangle has 3 angles inscribed circle center O . AD is the altitude , and AM is the median line of ABC triangle. d is the mid perpendicular of BC . Prove that :
a) If H is the Intersection of two lines AD and the line which links O and the focus G of ABC triangle then H is the orthocentre of ABC triangle
b) If G is the intersection of two lines : AM and the line which links the lines O and the orthocenter H of ABC triangle then G is the focus of the ABC triangle
lời giải : Here !
