tim tat ca cac so nguyen X sao cho:(x^2-10) (x^2+10)<0
cho A1,A2,A3,...,A100 trong do khong co 3 diem nao thang hang. goi S la tong cac doan thang nhan hai diem trong cac diem do lam dau mut. Hay so sanh S voi 5000
cho 20 diem phan biet , trong do co dung 7 diem thang hang , ngoai ra khong co 3 diem nao thang hang.cu qua 2 diem ta ve duoc 1 duong thang.hoi tu 20 diem do ta ve duoc bao nhieu duong thang
cho ab =12cm .goi c la trung diem cua ab.tinh ac cb? lay 2 diem de tren doan thang ab sao cho ab=be=5cm tinh cd ce? diem c co la trung diem cua doan de khong ?vi sao
Tren tia Ox lay diem M sao cho OM=1,5 cm. Tren tia doi cua tia Ox lay diem N va B sao cho ON=1,5 cm;OB=4,5 cm. Hoi diem N co la trung diem cua MB khong?
-ke ten cac cap goc ke bu nhau'
-so do goc QAP la bao nhieu
-ke ten cac cap goc ke bu
-co cap goc nao ke phuc nhau khong
cho góc bẹt xOy . trên cùng một nửa mặt phẳng bờ chứa tia xy , ve 2 tia OM , ON sao cho goc xON = yOM = 30 độ . vẽ tia phân giác OI cua goc MON .hoi OI co phai tia phan giac cua goc xOy khong ? vi sao?
1. Cho hai goc ke \(\widehat{AOB}\) va \(\widehat{BOC}\) co tong so do cua hai goc la \(^{140^0}\) biet \(\widehat{AOB}\) co so do lon hon so do cua goc \(\widehat{BOC}\) la \(^{20^0}\)
a, Tinh \(\widehat{AOB,}\widehat{BOC}\)
b, Ve tia phan giac Om cua \(\widehat{AOB}\), tia phan giac On cua \(\widehat{BOC}\). Tinh \(\widehat{mOn}\).
1) cho goc bet xoy ve tia oz sao chi goc yoz=60*
a) tinh so do goc zox
b) ve tia om, on lan luot la tia phan giac cua goc xozva yoz hai goc zom , zon co quan he gi giai thich