Các câu hỏi tương tự
Cho a+5/a-5=b+6/b-6 (a khac 5 b khac 6).Chung minh rang a/b=5/6
chung minh rang neu a,b,c la cac so khac 0 thoa man
ab+ac/2=bc+ba/3=ca+cb/4 thi a/3=b/5=c/15
cho a,b,c la 3 so thuc doi mot khac nhau va khac khong, thoa man: a+1/b=b+1/c=c+1/a. hay chung minh rang abc=1 hoac abc=-1
Chung minh rang neu cac so a,b,c khac 0 thoa man (ab+ac)/2=(bc+ba)/3=(ca+cb)/4 thi a/3=b/5=c/15
6-(x-1/3)^2=2^2013:(-2)^2012
Cho xBy=70°. Tren tia Bx lay diem A( A khac B), tren tia By lay diem C(C khac B). Goi M la trung diem cua AC. Qua A ke duong thang song song voi By cat tia BM tai D
a,chung minh ∆AMD=∆CMB
b, chung minh AB=DC
Ke BH vuong goc voi AD( H nam tren tia DA) . Tinh HBx
cho a,b thuoc N, a chia het cho 3 r1 khac 0
b chia het cho 3 r2 khac 0
biet r1 khac r2, chung minh rang [ a cong b] chia het cho 3
cho 2/a=1/b+1/c(a,b,c khac 0,a khac c).Chung minh rang b/c=b-a/a-c
bai 1:cho goc xOy la goc tu,trong goc nay ve cac tia Om,On sao cho Ox vuong goc voi On,Oy vuong goc voi Om.
chung minh rang goc xOy va goc mOn co trung tia phan giap
bai 2:cho goc AOB =150 do.ve trong goc nay hai tia Ox va Oy sao cho OA vuong goc voi Ox ,OB vuong goc voi Oy.tinh goc xOy?
bai 3:cho a+b/a-b=c+a/c-a voi a khac b,c khac a.chung minh a^2=b*c
chung minh rang neu a,b,c la cac so khac 0 thoa man ab+ac/2=bc+ba/3=ca+cb/4 thi a/3=b/5=c/15
mk dg can gap nha
ai lm dc (giai ki) mk tick cho