với x\(\ge0,xe1\) ta có A=\(\dfrac{x\sqrt{x}+1}{x-1}-\dfrac{x-1}{\sqrt{x}-1}=\dfrac{\left(\sqrt{x}\right)^3+1}{\left(\sqrt{x}-1\right)\left(\sqrt{x}+1\right)}-\dfrac{x-1}{\sqrt{x}-1}=\dfrac{\left(\sqrt{x}+1\right)\left(x-\sqrt{x}+1\right)}{\left(\sqrt{x}-1\right)\left(\sqrt{x}+1\right)}-\dfrac{x-1}{\sqrt{x}-1}=\dfrac{x-\sqrt{x}+1}{\sqrt{x}-1}-\dfrac{x-1}{\sqrt{x}-1}=\dfrac{x-\sqrt{x}+1-x+1}{\sqrt{x}-1}\dfrac{2-\sqrt{x}}{\sqrt{x}-1}\)vậy=.