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 so nguyen duong x;y;z thoa man x!+y!=10.z+9
tim cap so nguyen (x;y) thoa man : |x+2| + (y+2)2 = 3 - |x+1|
tim tat ca cac so nguyen duong x,y thoa man : 2011x+7y=42231
tim cac so x y z nguyen duong thoa man x3+3x2+5=5y va x+3=5z
Tim cac so nguyen thoa man (x+y)^2=(x-1)(y+1)
tim cap so nguyen x,y thoa man: |x+4|+|y-2|=3
Tim 3 so nguyen to lien tiep x,y,z (x<y<z) thoa man A = x^2 + y^2 + z^2 la so nguyen to