One Dream

 $\left\{\begin{matrix} xy+2=y\sqrt{x^{2}+2} & \\ y^{2}+2(x+1)\sqrt{x^{2}+2x+3}=2x^{2}-4x& \end{matrix}\right.$

Giải Pt $Sin^{2012}x+Cos^{2012}x=\frac{1}{2^{1005}}$

Cho x,y,z$\geq 0 : \sqrt{1+x^{2}}+\sqrt{1+2y}+\sqrt{1+2z}$=5

Tìm $P max= 2x^{3}+y^{3}+z^{3}$