KingClashOfClansVietNam

cho tam giac nhon abc.AD la duong cao,h la truc tam , g la trong tam tam giac

1.CMR:tanB.tanC=AD/HD

2.khi hg song song bc.CMR:tanB.tanC=3

 TKS!!!
       

cho hinh binh hanh abcd diem m thuoc canh bc ,diem n thuoc tia doi cua tia bc sao cho bn=cm. cac duong thang dn,dm cat ab lan luot tai e,f.CM

a.AE^2=EB.FE

b.EB=(AN/DF)^2.EF

tim cac so x,y nguyen duong thoa man phuong trinh sau:

3x^2+2y^2-7xy+3x-y-47=0        

tren bang nguoi ta viet cac so tu nhien lien tiep tu 1 den 100 sau do thuc hien tro choi nhu sau:moi lan xoa 2 so bat ki va viet mot so moi bang tong lap phuong 2 so da xoa.thuc hien tro choi den khi con 1 so tren bang.hoi so do co the la 123^1819 ko?