1 tam giac vuong co chu vi la 30 cm , do dai hai canh goc vuong hon kem nhau 7 cm .tinh do dai cac cach cua tam giac vuong do
1. cho tam giac ABC M;N lan luot la trung diem cua CA ,CB ;I la diem bat ki tren MN (I khac M;N ) C/M trong 3 tam giac ICB;ICA;IAB; co 1 tam giac ma dien tich cua no bang tong cac dien tich cua 2 tam giac con lai
2. cho tam giac ABC tren cac canh AB;AC;CA keo dai ve phia B;C;A lay B1;C1;A1 sao cho BB1=b;CC1=c; AA1=a c/m a/AC+b/ AB+c/BC>HOAC =3
tim tat ca cac canh va goc chua biet cua tam giac vuong do, cho tam giac abc vuong tai a co: b) BC=12, goc B= 35 do.
c) AC=4, goc C=42 do,
d) AB=15, BC=25
e) AB=6, goc C= 60 do
cho hinh thang abcd vuong tai a co canh day ab bang 6cm, canh ben ad bang 4cm va duong cheo vuong goc voi nhau. tinh do dai cac canh dc, cb va duong cheo dc
cho tam giac abc co ab=6 ac=8 goc a=30
tinh cac canh va cac goc con lai
tinh do dai cac duong trung tuyen
Cho tam giac ABC vuong tai A cac duong phan giac trongbAE ,BD cat nhau tai I cho IB bang 10 can5 ID bang 5can 5 tinh cac ti so AB/AD , CB/CD tinh ba canh cua tam giac ABC
cho tam giac ABC co 3 goc nhon cac duong cao AD BE CF cua tam giac ABC cat nhau tai H
a) CM: tu giac CFHD noi tiep trong 1 duong tron xac dinh vi tri tam O cua duong tron ngoai tiep tu giac CEHD
b) CM: goc FEH bang goc DEH . CM: H la tam duong tron noi tiep tam giac DEF
c) CM; CH = 4cm tinh do dai duong tron tam (o) va duong kinh hinh tron (o)
giai ho minh bai nay voi
cho a,b,c la do dai 3 canh tam giac va an;bn;cn cung la do dai 3 canh tam giac voi n la so nguyen duong. Chung minh rang 2 trong 3 so a,b,c bang nhau
Cac anh cac chi oi giup em voi, gap lam.Cho ham so y=x+1 co do thi la (d) va ham so y= -x+3 co do thi la (d' )
a) Ve (d) va (d' ) tren cung mot mat phang toa do
b) Hai duong thang (d) va (d' ) cat nhau tai C va cat truc Ox theo thu tu tai A va B tim toa do cac diem A,B,C (Tim toa do diem C bang phuong phap dai so)
c) tinh chu vi va dien tich tam giac ABC (voi don vi do tren cac truc toa do la cm)
d) tinh goc tao boi duong thang y=x+1 voi truc Ox
Cam on nhieu.