cho tam giac ABC (AB<AC) noi tiep duong tron tam (O) co truc tam la H.tia AH cat duong tron tam (o) o M .ke duong kinh AON
a)CM :MN//BC
b)goc BAM=goc CAN
c) goi I la trung diem cua BC. CM 3 diem H,I,N thang hang
d)tiep tuyen A cat BC tai E .CMR EB/EC=AB2/AC2
e)BH cat duong tron tai Q. cm 3 diem M,H,Q cung thuoc duong tron tam C
GIÚP MÌNH VỚI