已知 x,y,zx,y,zx,y,z 为正实数,且x+y+z=1x+y+z=1x+y+z=1,求证:
2xy+z≤x+2(y+z)+3(xz+xy−yz)4(y+z)\sqrt{\dfrac{2x}{y+z}}\le \dfrac{x+2(y+z)+3(\sqrt{xz}+\sqrt{xy}-\sqrt{yz})}{4(y+z)}y+z2x≤4(y+z)x+2(y+z)+3(xz+xy−yz)
我推了好久好久好久还是不会,求大佬们帮帮忙吧