1. Cho \(\Delta\)ABC co AB=AC.Tia phan giac cua goc A cat Bc tai D.Lay E tren AD.Chung minh:a) \(\Delta AEB=\Delta AEC\)b) AD\(\perp\)BC2. Cho \(\Delta\)ABC (AB<AC).Goi M la trung diem cua BC, tren tia AM lay D sao cho AM=MDa) Chung minh:\(\Delta AMB=\Delta DMC\)b)Chung minh: AB//CDc)Ve AI\(\perp\)BC tai I va DK \(\perp BC\)tai K..Chung...
Đọc tiếp
1. Cho \(\Delta\)ABC co AB=AC.Tia phan giac cua goc A cat Bc tai D.Lay E tren AD.Chung minh:
a) \(\Delta AEB=\Delta AEC\)
b) AD\(\perp\)BC
2. Cho \(\Delta\)ABC (AB<AC).Goi M la trung diem cua BC, tren tia AM lay D sao cho AM=MD
a) Chung minh:\(\Delta AMB=\Delta DMC\)
b)Chung minh: AB//CD
c)Ve AI\(\perp\)BC tai I va DK \(\perp BC\)tai K..Chung minh:MI=MK
