Các câu hỏi tương tự
cho tam giac ABC co M la giao diem ba duong trung tuyen chung minh rang neu MA=MB=MC thi tam giac ABC deu
chung minh: trong mot tam giac neu co 3 duong trung tuyen bang nhau thi do la tam giac deu
Cho tam giac deu ABC co canh = 3cm, M la diem bat ki trong tam giac ABC. Qua M ke cac duong song song voi AB, BC, CA, chung cat BC, CA, AB theo thu tu o A', B', C'. Ta co MA'+ MB'+ MC' =
chung minh rang neu mot tam giac co 2 duong trung tuyen bang nhau thi tam giac do la tam gac can
cho tam giac abe m la trung diem bc biet ma=mb=mc chung minh tam giac abc la tam giac vuong
cho tam gia abc co m la mot diem bat ki trong tam giac. chung minh: MA+MB+MC
a) lon hon nua chu vi tam giac abc
b) nho hon chu vi tam giac abc
Cho tam giac ABC vuong tai M la trung diem cua BC chung minh MA=MC=MB
c/m rang tong cua ba duong trung tuyen cua mot tam giac lon hon 3/4 chi vi nhung nho hon chu vi cua tam giac do
c/m rang trong tam giac vuong, trung tuyen ung voi canh huyen bang nua canh huyen
c/m rang: neu mot tam giac co trung tuyen thuoc mot canh bang nua canh ay thi tam giac do la tam giac vuong
cho tam giac ABC nhon goi H,G, . O theo thu tu la truc tam, trong tam ,giao diem cua ba duong trung tuyen cua tam giac.Tia AG cat BC o M Goi I la trung diem cua GA.K la trung diem cua GH chung minh
a) OM=1/2AH
b)tam giac IGK= tam giac MGO
c) 3 diem H,G,O thang hang
d)GH=2GO