

Cho các số dương x,y,z. CMR BĐT
[tex]\frac{(x+1)(y+1)^2}{3\sqrt[3]{z^2x^2}+1} + \frac{(y+1)(z+1)^2}{3\sqrt[3]{x^2y^2}+1} + \frac{(z+1)(x+1)^2}{3\sqrt[3]{y^2z^2}+1} \geq x+y+z+3[/tex]
[tex]\frac{(x+1)(y+1)^2}{3\sqrt[3]{z^2x^2}+1} + \frac{(y+1)(z+1)^2}{3\sqrt[3]{x^2y^2}+1} + \frac{(z+1)(x+1)^2}{3\sqrt[3]{y^2z^2}+1} \geq x+y+z+3[/tex]