ĐKXĐ: `(x-y)(\sqrt{x^3}+x)\ne 0`
`=> ` $\begin{cases}x-y\ne 0\\ x\sqrt{x}+x\ne 0\\\end{cases}$`<=>` $\begin{cases}x\ne y\\ x\ne 0\\ x,y\ge 0\\\end{cases}$
Rút gọn:
`\frac{(\sqrt{x}+1)(x-\sqrt{xy})(\sqrt{x}+\sqrt{y})}{(x-y)(\sqrt{x^3}+x)}`
`=\frac{(\sqrt{x}+1)[\sqrt{x}(\sqrt{x}-\sqrt{y})](\sqrt{x}+\sqrt{y})}{(\sqrt{x}+\sqrt{y})(\sqrt{x}-\sqrt{y})(x\sqrt{x}+x)}`
`=\frac{(\sqrt{x}+1)\sqrt{x}}{x(\sqrt{x}+1)}`
`=\frac{\sqrt{x}}{x}`