Các câu hỏi tương tự
cho tam giac abc co a=120o ad la duong phan giac. chung minh rang 1/ab+1/ac=1/ad
cho tam giac abc co a=120o ad la duong phan giac. chung minh rang 1/ab+1/ac=1/ad
1, Cho Tg ABC nhon: Co BC=a;AC=b;Ab=c. Duong phan giac AD.
a,Tinh BD;DC theo a,b,c.
b, Tia phan giac goc ABC cat AD o I. Tinh ti so AI/DI
c, Cho BC=(AB+AC):2.Goi G la trong tam cua tam giac ABC . C/m IG//Bc
cho tam giac ABC nhon co 3 duong cao AD , BE , CF cat nhau tai H CMR a)DB*DC=DH*DA.b)tam giac ABC dong dang voi tam giac AEF.c)DH/AD +HE/BE+HF/CF=1.d) H la giao diem cac duong phan giac cua tam giac DEF
Cau 1: Cho tam giac ABC cuong tai A, AB8cm; AC15cm. Ve duong cao AHa) chung minh AB^2 BH. BCb) Tinh BH, CH, AH, BCc) Ve phan giac AD cua tam giac ABC. Chung minh H nam giua B va Dd) Tinh ti so dien tich D HAC va D A.BCCau 2: Cho tam giac ABC vuong tai A, AB5cm; Ac12cm, ve duong cao AH va duong phan giac AD.a) Tinh BC, BDb) Chung minh D ACH: D ABC; tinh AHc) Qua B ke duong thang vuong goc voi AB cat tia AD tai K. Chung minh AB.AD AC. KD.Cau 3: Cho tam giac ABC vuong A co AB 5cm; AC12cm. Ve dcao...
Đọc tiếp
Cau 1: Cho tam giac ABC cuong tai A, AB=8cm; AC=15cm. Ve duong cao AH
a) chung minh AB^2= BH. BC
b) Tinh BH, CH, AH, BC
c) Ve phan giac AD cua tam giac ABC. Chung minh H nam giua B va D
d) Tinh ti so dien tich D HAC va D A.BC
Cau 2: Cho tam giac ABC vuong tai A, AB=5cm; Ac=12cm, ve duong cao AH va duong phan giac AD.
a) Tinh BC, BD
b) Chung minh D ACH: D ABC; tinh AH
c) Qua B ke duong thang vuong goc voi AB cat tia AD tai K. Chung minh AB.AD =AC. KD
.Cau 3: Cho tam giac ABC vuong A co AB = 5cm; AC=12cm. Ve dcao AH va pgiac AD cua goc BAC
a) Tih BC; BD
b) Chung minh D HAC : D ABC
c) Qua B ke duong vgoc voi BA cat AD tai k. Chung minh AB.AD= AC.KD
cho tam giac ABC co AB=6cm,AC=9cm,phan giac AD,duong trung truc AD cat AC tai E,tinh DE
CHO TAM GIAC ABC, DUONG CAO AD, H LA 1 DIEM BAT KI NAM TREN AD. BH CAT AC TAI E. CM CAT AB TAI F
CMR:
1) HD/AD+HE/BE+HF/CF=1
2) CM: DA LA PHAN GIAC CUA GOC EDF
Giup em voi can gap!!!!!!bai 1: Tam giac abc deu, ABa. M nam trong tam giac. A,B,C lan luot la hinh chieu cua M tren BC, AC ,AB. Tinh MA + MB +MC va AC + BA +CBBai 2:tam giac abc, goc a 90. ABc,ACb, phan giac AD. Tinh 1/c + 1/b theo ADBai 3:Hinh vuong ABCD canh a. M thuoc BC, AM giao DC tai P, DM giao AB tai Q, BP giao CQ tai i. Cho CM 1, Tinh Bi, Ci theo aBai 4:tam giac ABC, BC40, Phan giac AD45, duong cao AH 36. Tinh BD, CDBai 5:Tam giac ABC vuong tai A, phan giac goc B va Goc C giao nhau ta...
Đọc tiếp
Giup em voi can gap!!!!!!
bai 1:
Tam giac abc deu, AB=a. M nam trong tam giac. A',B',C' lan luot la hinh chieu cua M tren BC, AC ,AB. Tinh MA' + MB' +MC' va AC' + BA' +CB'
Bai 2:
tam giac abc, goc a = 90. AB=c,AC=b, phan giac AD. Tinh 1/c + 1/b theo AD
Bai 3:
Hinh vuong ABCD canh a. M thuoc BC, AM giao DC tai P, DM giao AB tai Q, BP giao CQ tai i. Cho CM =1, Tinh Bi, Ci theo a
Bai 4:
tam giac ABC, BC=40, Phan giac AD=45, duong cao AH = 36. Tinh BD, CD
Bai 5:
Tam giac ABC vuong tai A, phan giac goc B va Goc C giao nhau tai i, hinh chieu cua iB, iC tren BC lan luot la m va n. tinh dien tich tam giac ABC theo m,n
cho tam giac abc vuong tai a duong phan giac bd biet ab = 6 ac =8 tinh ad dc goi k la giao diem cua duong cao ah ba bd chung minh tam giac ahb dong dang voi tam giac cab chung minh abk dong dang voi tam giac bad tu do suy ra ab*bk = bd*hb giup mik voi