X
xyz_009


Cho a,b,c là các số dương . Cmr
[TEX]\frac{ab}{a+3b+2c}+\frac{bc}{b+3c+2a}+\frac{ca}{c+3a+2b}[/TEX]\leq[TEX]\frac{a+b+c}{6}[/TEX]
[TEX]\frac{ab}{a+3b+2c}+\frac{bc}{b+3c+2a}+\frac{ca}{c+3a+2b}[/TEX]\leq[TEX]\frac{a+b+c}{6}[/TEX]