Cho tam giac ABC co 3 duong trung tuyen AM,BN,CP.Qua N ke duong thang song song voi PC cat BC tai F , duong thang qua F song song voi PN va duong thang qua B song song voi CP cat nhau tai D . Goi G la trong tam cua tam giac ABC .CMR : \(S_{ABG}=S_{GBC}=S_{GCA}\)
AM, BN, CP la cac duong trung tuyen cua tam giac abc cmr (AB+AC+BC)<3/4AM+BN+CP
Cho tam giac ABC co AB=24cm,AC=30cm,BC=36cm.Cac duong trung tuyen AM va BN cat nhau tai G.Goi O la giao diem cua cac duong phan giac AD va BE.Tinh AE,EC,BD,DC,OG?
Tam giac ABC co AB=a,AC=b AD la duong phan giac,AM la duong trung tuyen,D la trung diem MN, N thuoc BC.Tinh BN/NC
Cho tam giac ABC vuong o A, co AB = 5cm,BC = 13. 3 duong trung tuyen AM,BN,CE cat nhau tai O.
a, Tinh AM, BN, CE
b, Tinh dien tich tam giac BOC
Cho tam giac ABC vuong tai A . Ba duong trung tuyen AD BE CF. Ba duong trung tuyen AM , BN , CE cat nhau tai O
a tinh AM , BN , CE
b Tinh dt tam giac BOC
cho tam giac ABC vuong tai A,co AB=5cm,BC=13cm.Ba duong trung tuyen AM,BN,CE cat nhau tai O
a)tinh AM,BN,CE
b)tinh dien tich tam giac BOC
cho tam giac ABC vuong tai A co B >C. KE duong cao AH, duong trung tuyen AM va duong phan giac AD
gia su AH ,AM chia BAC thanh ba goc = nhau
1, CM AD cung la tia phan giac cua HDM
2, B =CAH 3, tinh B,C va HAD
cho tam giac ABC nhon/ AM;BN;CPla cac duong trung tuyen. qua N ke duong thang song song voi CP va cat nhau o D
a. CPNF la hinh gi ? vi sao?
b. chung minh BDFN la hinh binh hanh?
c.chứng minh PNCD là hình thang cân?
d chung minh AM=DN
e tam giac ABC can them dieu kien gi de PNCD la hinh thang can?