[tex]x\sqrt{1-y^{2}}+y\sqrt{2-z^{2}}+z\sqrt{3-x^{2}} = 3\\\rightarrow \frac{x^2}{2}-x\sqrt{1-y^{2}}+\frac{1-y^2}{2}+\frac{y^2}{2}-y\sqrt{2-z^{2}}+\frac{2-z^2}{2}+\frac{z^2}{2}-z\sqrt{3-x^{2}}+\frac{3-x^2}{2}=0\\\rightarrow \frac{1}{2}(x-\sqrt{1-y^2})^2+\frac{1}{2}(y-\sqrt{2-z^2})^2+\frac{1}{2}(z-\sqrt{3-x^2})^2=0\\\rightarrow ...[/tex]