Đáp án:
Giải thích các bước giải:
b) `B=\frac{2\sqrt{x}}{\sqrt{x}+1}-\frac{\sqrt{x}+2}{\sqrt{x}-1}+\frac{2\sqrt{x}+4}{x-1}`
ĐK: `x \ge 0, x \ne 1`
`B=\frac{2\sqrt{x}(\sqrt{x}-1)}{(\sqrt{x}-1)(\sqrt{x}+1)}-\frac{(\sqrt{x}+1)(\sqrt{x}+2)}{(\sqrt{x}-1)(\sqrt{x}+1)}+\frac{2\sqrt{x}+4}{(\sqrt{x}-1)(\sqrt{x}+1)}`
`B=\frac{2x-2\sqrt{x}-(x+3\sqrt{x}+2)+2\sqrt{x}+4}{(\sqrt{x}-1)(\sqrt{x}+1)}`
`B=\frac{x-3\sqrt{x}+2}{(\sqrt{x}-1)(\sqrt{x}+1)}`
`B=\frac{(\sqrt{x}-2)(\sqrt{x}-1)}{(\sqrt{x}-1)(\sqrt{x}+1)}`
`B=\frac{\sqrt{x}-2}{\sqrt{x}+1}`
