bai 1 tim cac stn x y z sao cho x+y+z=xyz
bai 2cmr neu m^2+mn+n^2chia het cho 9 voi m ,n la cac stn thi m,n chia het cho 3
bai 3 tim stn n nho nhat de cac phan so sau toi gian
7/n+9.8/n+10,...,31/n+33
bai 4chung to rang phan so m^3+2m/m^4+3m^2 +1 toi gian
bai 5 a,cmr khong ton tai so chinh phuong nao co dang abab
b,cho 51 so nguyen duong khong vuot qua 100 cmr ton tai 2 so trong 51 so noi tren ma 1 so chia het cho so con lai
c,tim cac so co 3 chu so sao cho hieu cua so ay va gom 3 chu so ay viet theo thu tu nguoc lai la mot so chinh phuong
bai 6cmr A=2x(x+y-1)+y^2+1 luon nhan gia tri khong am voi moi x,y
bai 7 tim hai so nguyen duong sao cho tong ,hieu thuong (so lon chia cho so nho )cua chung cong lai duoc 38
bai 8 cho ba so a,b,c thoa man a/2009=b/2010=c/2011
tinh gia tri cua bieu thuc M=4(a-b)(b-c)-(c-a)^2
Cho so nguyen to n co 2 chu so hang chuc la x, hang don vi la y. Biet M=n/x+y. Tim n de M=2. Tim n de M dat gia tri nho nhat
A=1(x+3) - | 3x+2 |
a)rut gon A
b)tim x de A=5
Mik can rat gap giup mik di mik tick cho :(
3 dg cao trong tam gic ABC lan luot la 4,12,x biet x la 1 stn . tim x biet ( moi canh cua tam giac nho hon tong 2 canh kia va nho hon hieu 2 canh do
Tim so tu nhien nho nhat de cac phan so sau toi gian:1/n+3;2/n+4;3/n+5;...2001/n+2003;2002/n+2004
cho phân số A=6n-1/3n+2.tim n thuoc Z de A co gia tri nho nhat
rut gon bieu thuc 10n+1 -6*10n
bai 1: a) tim p/s co mau so bang 10, lon hon -7/13, nho hon -4/13
b) tim 10 so a/b biet -1/2<a/b<1/2
c) tim cac p/s -3/5<a/20<-1/4
ai tra loi nhanh va dung mk tick cho
Rut gon bieu thuc(2014.2015-1)/(2013.2015+2014) duoc ket qua la: