[tex]x^2+3-2\left ( \sqrt{x}+\frac{1}{\sqrt{x}} \right)\sqrt{x^2+3}+\left ( \sqrt{x}+\frac{1}{\sqrt{x}} \right)^2-\left ( \sqrt{x}-\frac{1}{\sqrt{x}} \right)^2=0<=>\left ( \sqrt{x^2+3}-\sqrt{x}-\frac{1}{\sqrt{x}} \right)\left ( \sqrt{x^2+3}+\sqrt{x}+\frac{1}{\sqrt{x}} \right)=0=>\sqrt{x^2+3}-\sqrt{x}-\frac{1}{\sqrt{x}}=0=>\sqrt{x^2+3}=\sqrt{x}+\frac{1}{\sqrt{x}}<=>x^2+3=x+\frac{1}{x}+2<=>x^3+x-x^2-1=0[/tex]