cho x,y,z la cac so huu ti duong thoa man x+1/yz y +1/xz z+1/xy la cac so nguyen tim gia tri lon nhat cua bieu thuc A=x+y^2+z^3
tim cac gia tri nguyen cua x de gia tri bieu thuc y=2x^2+1/2x-1 la so nguyen
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
Tim cac gia tri nguyen cua x de cac gia tri bieu thuc sau la so nguyen
a, 9-2x/x-3
b,3x-5/x-2
c,-3/4-x
Tim cac so nguyen thoa man (x+y)^2=(x-1)(y+1)
1) tim GTNN cua cac don thuc a)x^2 - 4xy + 5y^2 - 2y + 3
b)x^2 - 2xy + 2y^2 - x +y
tim cac gia tri nguyen cua x de cac gia tri bieu thuc sau la so nguyen
a,9-2x/x-3
b,3x-5/x-2
c,-3/4-x
tim cac so nguyen x, y thoa man x>y>1 va 2x + 2y + 1 chia het cho xy
tim moi so nguyen to thoa man x^2-2y^2=1