1:Cho x;y>0:\(\frac{2}{x}+\frac{3}{y}=6\).Tìm min P=x+y
2:Cho x;y;z>0:x+y+z\(\le\)1.Chứng minh\(\sqrt{x^2+\frac{1}{x^2}}+\sqrt{y^2+\frac{1}{y^2}}+\sqrt{z^2+\frac{1}{z^2}}\ge\sqrt{82}\)
3:cho a;b;c;d>0.Chứng minh\(\frac{a^2}{b^5}+\frac{b^2}{c^5}+\frac{c^2}{d^5}+\frac{d^2}{a^5}\ge\frac{1}{a^3}+\frac{1}{b^3}+\frac{1}{c^3}+\frac{1}{d^3}\)
4:Tìm max,min y=x+\(\sqrt{4-x^2}\)
5:Cho \(a\ge1;b\ge1\).Chứng minh \(a\sqrt{b-1}+b\sqrt{a-1}\le ab\)
6:Chứng minh:\(\left(ab+bc+ca\right)^2\ge3\text{a}bc\left(a+b+c\right)\)