

cho $x,y,z$ không âm thay đổi.
CMR:
$\frac{1}{x+y+z+1}-\frac{1}{(1+x)(1+y)(1+z)}\leq\frac{1}{8}$
@Đoan Nhi427
@Blue Plus
@hdiemht
@Ann Lee
@iceghost
@lengoctutb
CMR:
$\frac{1}{x+y+z+1}-\frac{1}{(1+x)(1+y)(1+z)}\leq\frac{1}{8}$
@Đoan Nhi427
@Blue Plus
@hdiemht
@Ann Lee
@iceghost
@lengoctutb