\(A=\frac{\sqrt{x}^3}{\left(\sqrt{x}+1\right)\left(\sqrt{x}-1\right)}-\frac{\left(\sqrt{x}+1\right)\left(\sqrt{x}-1\right)}{\sqrt{x}+1}\)
\(=\frac{x\sqrt{x}}{\left(\sqrt{x}+1\right)\left(\sqrt{x}-1\right)}-\left(\sqrt{x}-1\right)=\frac{x\sqrt{x}-\left(\sqrt{x}-1\right)\left(x-1\right)}{\left(\sqrt{x}+1\right)\left(\sqrt{x}-1\right)}\)
\(=\frac{x\sqrt{x}-x\sqrt{x}+\sqrt{x}+x-1}{\left(\sqrt{x}+1\right)\left(\sqrt{x}-1\right)}=\frac{x+\sqrt{x}-1}{x-1}\)