goi M la 1 diem bat y cua doan thaang AB , diem M nam o dau hay chon cau tra loi dung
a) diem M phai trung voi diem A
b) diem M phai trung voi 2 diem A va B
c) diem M phai trung voi diem B
d) diem M hoac trung voi diem A hoac nam giua 2 diem A va B hoac trung voi diem B
1.mot nguoi du dinh di quang duong tu A den B trong 2 h .Gio thu nhat nguoi do di duoc 4/7 quang duong ,gio thu 2 nguoi do di 12km con lai .tinh khoang cach AB
2.tren quang duong AB dai 120 km co 2 nguoi di nguoc chieu nhau ,nguoi thu 1 di tu A voi van toc 60 km/h .sau do 15 p',nguoi thu 2 di tu Bvoi van toc 40km/h .sau 1h30p' ke tu luc nguoi thu 2 bat dau khoi hanh khoang cach giua 2 nguoi la bao nhieu km?
viet cac tap hop sau = cach chi ra tinh chat dac trung cho cac phan tu cua tap hop ?
a, tap hop X cac so tu nhien lon hon 0 va nho hon hoac bang 10 ?
b, tap hop Y cac so tu nhien co 2 chu so ?
c, tap hop M cac so tu nhien16 ; 25 ; 36 ; 49 ; 64 ; 81 ?
cho doan thang AB = 5cm va diem C nam giua 2 diem A va B sao cho CB = 3cm
a, tinh do dai doan thang AC
b, tren tia doi cua tia CA lay diem D sao cho CD = 5cm hay so sanh AC va BD
bai 1
a,trong phep chia cho 2 co so du co the bang 0 hoac bang 1 .trong moi phep chia cho 3,cho 4,cho 5,so du co the bang bao nhieu ?
b,dang tong quat cua so chia het cho 2 la 2k ,dang tong quat cua so chia cho 2 du 1 la 2k +1 voi k e N .hay viet dang tong quat cua so chia het cho 3 , so chia cho 3 du 1 ,so chia cho 3 du 2.
Mot hinh thang co dien tich 110 cm2 , hieu do dai hai canh day bang 6 cm. Neu tang day lon them 3 cm thi dien tich hinh thang se tang them 15 cm2 . Hoi :
a) Chieu cao cua hinh thang.
b) do dai mooi day hinh thang.
Mot hinh thang co dien tich 110 cm2 , hieu do dai hai canh day bang 6 cm. Neu tang day lon them 3 cm thi dien tich hinh thang se tang them 15 cm2 . Hoi :
a) Chieu cao cua hinh thang.
b) do dai moi day hinh thang.
tim cac so tu nhien x , biet :
a, x thuoc U(18) va x thuoc B(4)
b, x thuoc U(36) va x > hoac = 12
c, x thuoc B(12) VA 30 < HOAC = X < HOAC = 100
d, x thuoc U(28) va x thuoc U (21)
1) Co hai thùng dau.Neu chuyen 16l tu thung to sang thung nho thi so dau o hai thung bang nhau neu chuyen 1 l tu thung nho sang thung to thi thung gap to gap thung nho .Tinh so dau cua moi thung
2) x+x:0,5+x:0,25=14
3) mot hinh thang co dien tich 110cm vuong hieu do dai hai day =6cm . neu tang day lon them 3cm thi dien tich hinh thang se tang them 15cm vuong hay tinh
a) chieu cao cua hinh thang
b) do dai cua moi day cua hinh thang
4) 129,68*9.3+1296.8*0.07