P=$\sqrt{\frac{\sqrt{x}(x\sqrt{x}-1)}{x+\sqrt{x}+1}-\sqrt{\frac{\sqrt{x}(x\sqrt{x}+1)}{x-\sqrt{x}+1}}+x+1}=\sqrt{\sqrt{x}(\sqrt{x}-1)-\sqrt{x}(\sqrt{x}+1)+x+1}=\sqrt{x-\sqrt{x}-x-\sqrt{x}+x+1}=\sqrt{x-2\sqrt{x}+1}=\sqrt{(\sqrt{x}-1)^{2}}=\left| {\sqrt{x}-1} \right|=1-\sqrt{x}$ (vì $0\leq x\leq 1$ nên $1-x\geq0$
P=$\sqrt{\frac{\sqrt{x}(x\sqrt{x}-1)}{x+\sqrt{x}+1}-\sqrt{\frac{\sqrt{x}(x\sqrt{x}+1)}{x-\sqrt{x}+1}+x+1}}=\sqrt{\sqrt{x}(\sqrt{x}-1)-\sqrt{x}(\sqrt{x}+1)+x+1}=\sqrt{x-\sqrt{x}-x-\sqrt{x}+x+1}=\sqrt{x-2\sqrt{x}+1}=\sqrt{(\sqrt{x}-1)^{2}}=\left| {\sqrt{x}-1} \right|=1-\sqrt{x}$ (vì $0\leq x\leq 1$ nên $1-x\geq0$
P=$\sqrt{\frac{\sqrt{x}(x\sqrt{x}-1)}{x+\sqrt{x}+1}-\sqrt{\frac{\sqrt{x}(x\sqrt{x}+1)}{x-\sqrt{x}+1}
}+x+1}=\sqrt{\sqrt{x}(\sqrt{x}-1)-\sqrt{x}(\sqrt{x}+1)+x+1}=\sqrt{x-\sqrt{x}-x-\sqrt{x}+x+1}=\sqrt{x-2\sqrt{x}+1}=\sqrt{(\sqrt{x}-1)^{2}}=\left| {\sqrt{x}-1} \right|=1-\sqrt{x}$ (vì $0\leq x\leq 1$ nên $1-x\geq0$