a)$...= \frac{x\sqrt{x}+x-x}{x+\sqrt{x}}.\frac{\sqrt{x}(x-1)}{\sqrt{x}-1}$$=\frac{x\sqrt{x}}{\sqrt{x}(\sqrt{x}+1)}.\frac{\sqrt{x}(\sqrt{x}-1)(\sqrt{x}+1)}{\sqrt{x}-1}$$=x\sqrt{x}$
a)$...= \frac{x\sqrt{x}+x-x}{x+\sqrt{x}}.\frac{\sqrt{x}(x-1)}{\sqrt{x}-1}$$=\frac{x\sqrt{x}}{\sqrt{x}(\sqrt{x}+1)}.\frac{\sqrt{x}(\sqrt{x}-1)(\sqrt{x}+1)}{\sqrt{x}-1}$$=x\sqrt{x}.\sqrt{x}=x^2$
a)$...= \frac{x\sqrt{x}+x-x}{x+\sqrt{x}}.\frac{\sqrt{x}(x-1)}{\sqrt{x}-1}$$=\frac{x\sqrt{x}}{\sqrt{x}(\sqrt{x}+1)}.\frac{\sqrt{x}(\sqrt{x}-1)(\sqrt{x}+1)}{\sqrt{x}-1}$$=x\sqrt{x}$