tim cac so x,y thoa man :2x^2+y^2-2y=2(xy-1)
tim cac so huu ti x y thoa man x+y va 1/x +1/y nguyen duong
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 cap so nguyen x , y thoa man : 2 . ( xy - 3 ) = x
Tim cac so nguyen thoa man (x+y)^2=(x-1)(y+1)
tim so nguyen x,y thoa man mot trong cac dieu kien sau
a,37+(13-/2x+7/)=630*(914.415)
b,(x-7).(x+3)<0
c,xy+3x-2y=11
tim cac so nguyen x,y thoa man: 1/x-1/3=1/y voi x,y khac 0
tim x va y thoa man: x^2 - xy -2y^2 - 1 = 0
Tim hai so huu ti x va y sao cho cac phan so dai dien co mau la 13, cac tu so la hai so nguyen le lien tiep thoa man dieu kien:x<4/5<y