a)Tim tat ca cac so nguyen duong x, y , z thoa man: \(\frac{x+y\sqrt{2013}}{y+z\sqrt{2013}}\)la so huu ti, dong thoi x2 + y2+ z2 la so nguyen to.
b) Tim so tu nhien x, y thoa man: x(1+x+x2) = y(y-1).
a)Tim cap (x,y) nguyen duong thoa man xy=3(y-x)
b)cho 2 so x,y >0 thoa man x+y = 1
Tim GTNN cua M=(x^2+1/y^2)(y^2+1/x^2)
cho x y la hai so nguyen duong khac nhau thoa man \(2x^2+x=3y^2+y\)
chung minh\(\frac{x-y}{2x+2y+1}\)la phan so toi gian
cho x,y là các số nguyên khac 1 thoa man (x2-1)/(y+1)+(y2-1)/(x+1) la so nguyen. chung minh rang x2 y22 - 1 chia het cho x+1
cho x,y,z la cac so thuc duong thoa man x+y+z=1 tim min A=x^3/(x^2+xy+y^2)+y^3/(y^2+yz+z^2)+z^3/(z^2+zx+x^2)
5x-2√x(2+y)+y^2+1=0
Tim cap so x,y thoa man dieu kien tren
Giup di lam on.....
tim cap so x,y thoa man:
5x-2canx(2+y)+y^2+1=0
Tim tat ca cac cap so nguyen(x,y) thoa man:
10x + y = x2 + y2 +1
Cho x,y,z la cac so thuc duong thoa man xyz=2
Chung minh rang:\(\frac{x}{2x^2+y^2+5}+\frac{2y}{6y^2+z^2+6}+\frac{4z}{3z^2+4x^2+16}\le\frac{1}{2}\)
