Cmr \(\frac{x-y}{1+xy}+\frac{y-z}{1+yz}+\frac{x-z}{1+xz}=\frac{\left(x-y\right)\left(y-z\right)\left(x-z\right)}{\left(1+xy\right)\left(1+yz\right)\left(1+xz\right)}\)
cho x+y+z=1 CMR : \(\sqrt{\frac{xy}{z+xy}}+\sqrt{\frac{yz}{x+yz}}+\sqrt{\frac{xz}{y+xz}}\le\frac{3}{2}\)
Cho x+y+z =1 CMR \(\sqrt{\frac{xy}{z-xy}}+\sqrt{\frac{yz}{x-yz}}+\sqrt{\frac{xz}{y-xz}}\le\frac{3}{2}\)
cho \(0\le x;y;z\le1.\)CMR:\(\frac{x}{1+y+xz}+\frac{y}{1+z+xy}+\frac{z}{1+x+yz}\le\frac{3}{x+y+z}\)
Cho \(0\le x,y,z\le1\). CMR:
\(\frac{x}{1+y+xz}+\frac{y}{1+z+xy}+\frac{z}{1+x+yz}\le\frac{3}{x+y+z}\)
Cho 0<x<y<z<1.CMR:
\(\frac{x}{yz+1}+\frac{y}{xz+1}+\frac{z}{xy+1}\le2\)
Cho x,y,z là độ dài 3 cạnh của tam giác. CMR
\(\frac{1}{x^2+yz}+\frac{1}{y^2+xz}+\frac{1}{z^2+xy}\le\frac{x+y+z}{2xyz}\)
Chứng minh rằng :
\(\frac{x-y}{1+xy}+\frac{y-z}{1+yz}+\frac{z-x}{1+xz}=\frac{\left(x-y\right)\left(y-z\right)\left(z-x\right)}{\left(1+xy\right)\left(1+yz\right)\left(1+xz\right)}\)
Cho \(xy+yz+xz=0\left(x,y,z\ne0\right)\).CMR \(\frac{1}{x^3}+\frac{1}{y^3}+\frac{1}{z^3}=\frac{3}{xyz}\)