Đáp án:
$B = \dfrac{3x +4\sqrt{x} +4}{x-4}$
Giải thích các bước giải:
$B = \dfrac{\sqrt{x} +1}{\sqrt{x} -2} +\dfrac{2\sqrt{x}}{\sqrt{x} +2} -\dfrac{2+5\sqrt{x}}{4-x}\\(x\ge0, x \ne4)\\ B = \dfrac{\sqrt{x} +1}{\sqrt{x} -2} +\dfrac{2\sqrt{x}}{\sqrt{x} +2} +\dfrac{2+5\sqrt{x}}{(\sqrt{x} -2)(2+\sqrt{x})}\\B = \dfrac{(\sqrt{x}+2)(\sqrt{x} +1)+2\sqrt{x}(\sqrt{x} -2)+2+5\sqrt{x}}{(\sqrt{x} -2)(\sqrt{x}+2)}\\B = \dfrac{x+\sqrt{x} +2\sqrt{x} + 2+2x -4\sqrt{x} + 2 +5\sqrt{x}}{x-4}\\B = \dfrac{3x +4\sqrt{x} +4}{x-4}$
